1. Idea Deathmatch: http://ideathmatch.com/
Determine what's better worldwide by voting between 2 things, similar to: http://either.io/
2. Nearby Instagram/Flickr: https://round.io//
Find Instagram pictures that were taken near you.
3. Lone Comment: http://lonecomment.com/
Use the front page to display anything you want, but you have to pay at least 10 cents more than the previous one, only one can be displayed.
4. Riddlewot: http://www.riddlewot.com/
If you answer the riddle correctly you are able to post the new riddle.
5. Quibbler: http://quibbler.co/
An anonymous chatroom where your comment fades away after a short time.
6. Quick Rant: http://quickrant.com/
See other Rants and post your own.
7. Random Act of Cards: https://www.reddit.com/r/randomactsofcards
A reddit thread where you can send and receive postcards from and to strangers.
8. Reddit Gifts: https://www.redditgifts.com/
Secret santa-like exchange with anonymous friends, you get paired with a stranger and you send something and receive something.
9. Is it Normal?: http://isitnormal.com/
A website where you can describe a situation and ask people if that's normal, you'll get statistics based on what you asked.
10. Communal Pixel Art: http://paint.reednj.com/
Giant Canvas where you paint with pixels.
11. Anondraw: http://www.anondraw.com/
A great website for artists, you can see anything that has been drawn by someone else or you can paint your own masterpiece.
12. Find Playdate: https://www.find-playdate.com/
Where nameless players are posting what games they want to play with someone, you can filter by platform, language and timezone.
13. Curve Fever: http://curvefever.com/
Interactive game where you make lines, kind of like the SNAKE game but with multiple players.
14. Manyland: http://manyland.com/
You can build an infinite landscape and interact with other users.
15. Typeracer: http://play.typeracer.com/
A fun typing game where you compete against other nameless drivers, the one who finishes first wins, also it'll give you your WPM.
16. Transformice: http://transformice.com/
A co-op game where you are a mouse and you have to get cheese and return to your mouse-hole.
17. Starbreak: https://www.starbreak.com/
18. Mienfield: http://mienfield.com/
A multiplayer minesweeper board.
19. Quadradius: http://quadradius.com/
It's checkers meets chess, players will take turns making a move and collecting abilities.
20. Multiplayer Puzzle: http://www.epuzzle.info/multiplayer
Solve the puzzle with a little help from your friends.