I dont know why this hasnt been posted before, maybe because the majority of members here are not from Japan.
http://regnessem.sourceforge.jp/eng/
It might not look like much there but check out what skins can do to it:
Go to Customize>Skins
Cool eh?!
Wow that site is awesome, Thanks for the link juno. =)
OMFG I did post that in the screenshot thread a loooong time ago! WTF did you think Holden and I were using? Rotten is the king of skinning Regnessem btw, but it's not that hard since it's mostly just images with no functions. Anyways, yea I love Regnessem but there are a few problems with it. Anyways, hope people like it. I stopped using it because I really wanted an AIM protocol for it but nobody ever made one. Check out my old screenshots for some inspiration for it 
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