One of big advantages of the internet is the ability to work from anywhere.  A number of  websites  offer crowdsourcing  / workers on demand .   Some of these websites are:

Amazon Mechanical turk – mturk.com – the oldest, you can use your Amazon login, offers payment in Indian Rupees. Has a large number of tasks available, usually in thousands for US residents.
Microworkers – microworkers.com – workers can appeal if a task is not approved, payment through Paypal , Moneybookers and check.
Cloudcrowd.com – need a Facebook account, offered daily payments through Paypal
Crowdflower.com
Jobboy.com
Simpleworkers.com
Shortask.com
Myeasytask.com
Humangrid.de (redirects to clickworker.com)
Minijobz.com
Rapidworkers.com
Domywork.net – for students
Minuteworkers.com
Iamoney.com
Saycomment.com
MyMicroJob.com

Payment for each task usually varies from 5 cents to a dollar and completed tasks are to be approved manually. After signing up on these websites for testing, there seems to be a lot of difference in the way these websites are run. Popular tasks involve signing up for programs, writing blog posts, manipulating social media, posting links. Some tasks are reserved for users from USA / Canada. You can earn a few dollars a month with these websites in your free time.