The following pixel artists produced Pixel Joint's top rated pixel art for April 2012. Many thanks go out to this month's top pixel artists and all the members who took time to rate.
philippejugnet challenges you to reinterpret a national flag as a scene. For example, you could create an Estonian forest from the Estonian flag:

Canvas Size - Unrestricted, however it must match the proportions of your chosen flag.
Colours - Unrestricted.
Transparency - Only if your chosen flag is non-rectangular (for example).
Animation - No.
Liberated Pixel Cup is a two-part competition: make a bunch of awesome free culture licensed artwork, and then program a bunch of free software games that use it. Liberated Pixel Cup brings together some powerful allies: Creative Commons, OpenGameArt, the Free Software Foundation, and you.
Create an advertisement in any format you want (billboard, TV advertisement, banner ad, etc...) for some kind of futuristic piece of technology.
Canvas Size - Unresticted.
Colours - Max 35.
Transparency - Optional.
Animation - Optional.
Love the pixel art in Sword & Sworcery? Well, the creators have announced CREATE IN THE KEY OF SWORCERY jam where they will showcase fan submitted media. What a great opportunity for Pixel Joint artists to show what can be done in our medium.
Kumiho, or nine-tailed fox in Korean, is PJer neofotistou's entry in Ludum Dare Jam, a 3 day game making contest and is a fresh and unique SHMUP game. The theme for this contest was 'Tiny Worlds".
Fez, the winner of this year’s IGF Grand Prize Award, is a non-linear puzzle platformer pixelart hybrid with some 3D voxel elements. Play as Gomez, a 2D creature on a voyage of discovery into the mysterious 3rd dimension. Change your perspective and look at the world in a different way.