I thought that I’d add a bigger list of short task sites and smartphone apps to the other sources of side income I recommend such as usability testing and selling stuff online. If you’re familiar at all with these sites, you’ll know that making a living off of them requires a lot of patience and knowledge of how the systems work. But if you’re looking to make a little extra spending cash, then signing up and sticking with one of them may prove to be just what you’re looking for.

Crowdsource Sites

Amazon mTurk: Read a review and some tips about finding decent paying HITs here. Pays you in US Dollars, Indian rupees, or Amazon gift certificates, depending on your location.
ClickWorker: This site provides workers with writing, translating, data entry, and research. Pays monthly in USD or Euros.
ClixSense: Microworkers earn cents for viewing ads, performing other small tasks, and by referring others to the site. What tasks are available depend on the profile of the worker. Pays twice weekly through PayPal, Payza, and Liberty Reserve. There is a minimum cash out.
Crowdflower: This company partners with other micro job sites like SwagBucks and Coinworker. There are a wide and varied array of tasks, all with fairly low pay, but they are short tasks that you can speed through.
CoinWorker: Users earn points which are then converted to Bitcoins once you hit 180 points. Bitcoins can be converted to currency, but there are fees associated with the conversion.
MicroWorkers: These jobs usually pay only a few cents each. Uses Moneybookers or Alertpay. Must have earned $9 to withdraw funds.
MobileWorks: When you start out, you are making a few cents per task, but it is possible to move up in the ranks and get higher paying tasks. The site also states that there are opportunities for management for their best workers. They pay using Paypal, Skrill, or you can work with them through oDesk.
RapidWorkers

Micro-Task Sites

A lot of these sites are clones of Fiverr.com. You’ll even notice the similarity in how the sites look. Unless otherwise noted, all sites pay $5 per completed task or service.

Dollar3: Work on this site can be sold in increments of $3, $5, $6, $9, $12, $15, $27, $45, and $90.
Fitty Town: This is a site like Fiverr.com, however you can post services starting at $40 to $50, rather than only $5. Pays through Paypal.
Fiverr: Users pay $5 for completion of services. Some people make a living off of Fiverr.com, but most use it as a side income source (like me!). If you’re hoping to be successful with Fiverr.com, I highly recommend the Fiverr Success program.
Gigbucks: Services range from $5 to $50.
SEO Clerks: Post any SEO related tasks or services.
Task Army: Another site where you can set your own rate.
TenBux: Post services for $5 or $10.
Tenrr: Similar to the other micro job sites, but they do not hold your earnings or take out any commissions!
Twentyville: This is Fitty Town’s sister site, with the difference being that you can post services starting at $10 with a maximum of $20.

Smartphone and Real World Micro-Tasks

Easyshift: Smartphone app. The types of task available include taking photos and doing price checks on certain products. Payments for tasks range from $2 to $20.
FieldAgent: Smartphone app. Jobs must be completed in 2 hours. Most jobs include price checks with photo and a bar code scan, mystery shopping, surveys, product reviews, business location verification, photos, and brochure placement. Pays $3-$12 per task.
Gigwalk: Smartphone app. You log on and find “gigs” or tasks, which can include price checks, app testing, data verification, taking photos, mystery shopping, and the like. Pays $3-$5 per gig.
Taskrabbit: Real-world micro tasks and virtual tasks. Both kinds of tasks are only available in certain cities. However, you can sign up to be notified when they get set up in your city. Some of the featured tasks are grocery shopping, food delivery, IKEA assembly, and donation pickup. I do hope this comes to my city soon! I’d love to be able to do some of these things!

Feel free to leave a comment about any sites I may have missed!

Here are a few books from Amazon about working for micro-task sites:

Making Money Online: How to Work From Home Virtually with Mechanical Turk
The Fiverr Master Class: The Fiverr Secrets Of Six Power Sellers That Enable You To Work From Home (Fiverr, Make Money Online, Fiverr Ideas, Fiverr Gigs, Work At Home, Fiverr SEO, Fiverr.com)
100 Ways to Make Money Online: A Guide to the ‘Net’s Top Freelance Marketplaces, Crowdsourcing Work Sites and Places to Sell Your Stuff