Gregg the Egg
From author's description: "Gregg the egg, hmmmm. GtE is a platform exploration game. That means that you jump and move around, gaining new powers, and getting further in the game. While the world in GtE isn't especially big, you will be facing many dangerous jumps, spikes, monsters and puzzles. The main character (gregg) evolves, gaining powers and awesomeness all along, hopefully keeping the gameplay interesting. If you're into like hardcore platforming, GtE is a game for you. If you don't know what to do, you can always youtube it to find one of tele's speedruns/hardcore mode videos. Have fun!"
There's a full walkthrough available here in .doc format, accompanied by a seperate pics file. (Local Mirror 23rd Jan '08)
There's also a video walkthrough courtesy of televids on YouTube:
There's also a five part hardcore mode on YouTube. Here's the first part of that: