Did you loose your job or are you on long-term disability or medical leave? Perhaps you're a soon to be mom (or dad!) who wants to stay home for the first year or so of their child's life and you'll need income than your spouse can provide alone.
Students also find themselves in this category - you need some additional income for spending money but you can't (or don't want to) find a job that will be flexible enough to work around your class schedule. No matter the case, if you've got a couple of months to a year before you need to see income from your efforts you've got a level of flexibility that really doesn't fit in to the 'make money online fast' scenario.
If this is the case for you, I'd recommend that you take your time and start an online business, correctly, from the start. If you have the time and energy and money to put into building a website, that's even better. Read up on the other parts of this site to fully explore your options and choose the best plan for you. Going about it this way will provide you with the largest income opportunity in the long run and be infinitely more sustainable than any of these other methods, which are time intensive and have a lower profitability.
I'd say that this is, when you sit down and really assess your options, where most people fall in the 'I need to make money online fast' category. You don't need to make money tomorrow or in the next couple of weeks, but you will need to make it soon.
Perhaps you've been laid off and have a month or so of severence pay. Perhaps you want to have extra money for the holidays. Perhaps you're unionized and you're far down on the 'call for work' list. Whatever the cause, if you don't think you can devote enough time to making an online business work (or you don't have the capital to get a website started) then consider one of the following options.
A Squidoo lens, an Ebay business, getting a work from home job part time or doing something like mystery shopping (yes, I know it's technically an offline job, but it is mostly done online). The return on these, especially if you get a part time work from home job, is more stable and requires a level of work intensity that makes it very doable for an extended period like a month or two, especially if you have another job at the same time.
Depending on the type of work involved, if you're willing to work part time there's a very low barrier to entry, even in the online market. However, there will be a delay in seeing some returns from any of these sources, so you should make sure you have some money stashed away to make it through until you start to see income. Some jobs, like blogging, can return as quickly as a week. Others will only pay bi-monthly or monthly.
Let's face it, you already know you're going to need more money to pay the rent a month from now. Something has happened, perhaps you lost your job or you had a medical emergency, but you need cash within the next 30 days. Here's my best suggestions for how to make that happen:
Develop an Ebay business. If necessary, use a drop shipper. Depending on your state, the paperwork to become a reseller can be completed within a week if done consertedly. Give yourself two weeks to get everything set up with your dropshipping services and during those two weeks list stuff around your house on Ebay. This will build your seller profile. Once your drop shipping service is in place, list like crazy - probably 1-5 items per day - and watch all your auctions like a hawk, making sure to give great customer service. Depending on how much time and effort you put into this, you can potentially turn around 100-1,000 in the month.
NOTE: don't bother drop-shipping cheap things. While these will sell quickly on eBay, the profit margin just isn't there. I would reccommend that most of your products retail for at least $50 if you want to see any money from them at all.
Alternatively, getting a short-term contracting gig for the month can be a great solution. Craigslist has an entire 'gigs' section. Don't just check your local Craigslist, but make sure to check all major metropolitan areas - if you're working online it doesn't matter your location.
If you're doing this or any of the following methods, make sure that you have a PayPal debit card so that you can access your cash FAST. These debit cards are convenient and free, eliminating the 3-day transfer wait as the money is sent to your bank account.
You need money to pay a bill, buy groceries, get your car out of hawk at the repair shop, or any other myriad number of reasons. But you need it this week. You don't have a month to get things set up or go without getting some cash.
Frankly, this is going to be very hard to do. It CAN be done, but it will require total concentration and effort. To make money online fast, you have to really put in the time- you can't just be sitting around on your couch hoping that money will fall from the sky.
Auctions and/or Craigslist are the way to go. You can make money online fast by list something today for a 5-day period on Ebay. It's not 'new' money, but you've liquidated an asset quickly.
Craigslist has tons of day-gigs if you're in any sort of major metropolitan area, especially on the weekends. While this isn't strictly online, many of these gigs will pay you same-day, thus getting you some cash quickly. These aren't the most interesting things ever, you'll have to be very humble, but it will make you quick cash.
Baring that, Craigslist and freelancewritinggigs.com list bunches of writing gigs that can be, if you're tenacious enough, applied for and turned around within the week. That's doable, but it's very dificult. I would only do this if you want to build your efforts to make money online fast into a long term work at home job.
Alternatively you can get into paid online surveys. This can be, depending on the company, turned around in a week or so between taking the survey and having the cash put in your PayPal account.
This used to be my worst-case scenario fear before my online business started to make good money: My car blows a gasket as my husband's driving home from work. We need cash to pay to have it towed (never mind fixed) and we have no credit cards (because our credit sucks). How do I get some money to see us through to tomorrow?
Thank God this never happened to me. I would probably have freaked out and hit up the International Bank of Parents because I would have not had enough clearheadedness to do something more productive.
HOWEVER, there are a couple things that you CAN do which will get turned around in about 24 hours. Make sure to read them closely if you need to make money online fast because you're in an emergency - you'll want to know how long this will take you.
I would suggest writing content for some of the websites out there that require simply the lowest common denominator of skill. They're content generation machines. The newer and lesser well known ones will be less descriminating. With a shorter review process, this has the potential to help you make money online fast.
The drive to make money quickly will limit your income level because it will require you to work at someone else's pay rate instead of creating a sustainable income for yourself. For this reason, it's better to only use these models if you're in dire straits and need to make ends meet. Save yourself some room in your day for developing your own ways to make money online so that you can create long term value for yourself and your family. However, I found that when you make money online fast, with some hard work it's possible to achieve $100-$500 per week in income. Remember, however, that these numbers are SOLEY dependent on your abilities, time and resources. So if you are limited in any of these areas, expect that you'll be on the lowest end of this range.