I'm not sure what the rules here are for self-promotion so I won't do this too often, but here's a batch of interesting videos you may want to check that I posted over the last two weeks:
Clockwork Knight longplay. No damage, no deaths, and a bunch of secrets uncovered. I've subtitled the opening song lyrics and the bit of story near the end. Still need to sub the closing song.
http://youtu.be/_0yjocajMCM
Clockwork Knight 2 longplay. No damage, no deaths, and even more secrets. Keep your eyes open for the hidden cameo near the end featuring '90s idol Hiroko Nakayama. Subtitles to be added later.
http://youtu.be/93w8QpSXPeU
Minigames from
Pepperouchau's Lucky Box. These are hidden on the disc. Can be unlocked by pressing "up, up, right, right, down, down, left, left, x, y, z" at the Bosses Galore title screen.
http://youtu.be/n-PlVhdbJdw
The Birth of Pepperouchau Movie. Another hidden extra from the Lucky Box collection. CG movie that wasn't used in either of the first two games. I'm guessing it was probably used as a proof-of-concept film. Watch for the Sonic cameo and the box right above him that literally says "cameo." Lyrics have been subtitled.
http://youtu.be/CxGF0BlcQiE
Clockwork Knight Puzzle (Pengin War). An unreleased prototype that was briefly circulated about 10 years ago before being yanked because a certain someone in the Sega community tried to resell copies of the ISO on Yahoo! Japan Auctions. Plays like a more elaborate version of Sega's earlier block-moving puzzle game Pengo.
http://youtu.be/wlqGXttrLFA
Enjoy!