Desktop Ponies is a program made by DesktopPonyGuy !i7LqknW0MA which creates a number of ponies which will roam the user's desktop, it is also possible to make the ponies play Pong or Soccer. As of Version 1.38.1, ponies will sometimes say things when interacted with. Almost any pony in the show can be used in this program, and one can also add custom ponies they or someone else has made. This program is also the source for many of the pseudo-8-bit and pseudo-16-bit like pony images, or "sprites". This programs also appears on several tumblr blogs. In addition, Derpy and Carrot Top have made several apperances on Ponychan, and Derpy is still circulating around the boards with a mechanism that remained unknown for many months. It was later revealed that the mystery Derpy sprite appears on a page at a probability factor of .01%.
The program is open sourced and is commonly accepted as the most widely adopted project to come out of /collab/. Due to its intentionally low resolution visuals, artists with even limited animation knowledge have found it easy to hop in and support such a solid program, knowing there isn't much to lose if it means scrapping or replacing their tweens.
A popular youtube series, Ponies Anthology, led by ZephyrStar, has utilized and credited the Desktop pony sprites for the use of their credits pages and intros.