Ya. I know another one which is shorttask.
For the full list of sites similar to microworkers you can go to http://goo.gl/oam5E
www.mp3locker.net
yes, they are only similar though. they are: facebook and bebo
Sites that are similar to Chem4Kids are The Science Spot and Science Kids. Chem4Kids is a website that teaches the basics of chemistry using fun quizzes.
www.apartments.com is very similar to apartmentguide.com
some other sites are 1227.com, a knockoff version of youtube, octopusgirl.com, lemonparty.com, meatspin.com, and there are probably more sites than that, but these r the ones I know.
There are lots of other sites like Phazeddl. Katz CD, Phazemp3, Dl4all, DownloadPost and Icedll are all some similar sites where one can one can download.
I guess 'amen' is similar in some sense, also there is a site called 'sodahead'..
They are both sites of pilgrimage. Other than that, they bear no similarities.
The website imeem or you can find more similar sites by doing similar site search to projectplaylist.
If you go to MapQuest and some other similar sites you can get directions on a map and in words.
Try these sites: similarsitesearch.com similarsites.com moreofit.com
There are a number of website that are similar to Hispasphere. Some of the more popular ones are EliteFreak, EMule, TomaDivx, Sharemula and Bittorrent.