Micro ATX Geekery HELP!

Ok guys, I love my geeks, I know you guys can help me out there.

I have the sudden urge to build a micro ATX HTPC. I want it to be in slimline form factor, with sexy LED lights for no reason and clear acrylic windows. I know how cheesy that sounds, but I'm really eager to begin buying proper parts to make this dream a reality. This will be the first PC i'll have the money to build! I've built mny other PCs before but with spare parts from the military base nearby and from old computers. I need this to be able to at least play 720p MKV files which I know any modern CPU should be able to handle, but my worries are with the heat issue, I don't want the little shit to over heat because of the smaller case. I'd like to have HDMI output, but I need some help on where to look.

Which CPU and Micro ATX board are the best for this and what kind of PicoPSU should I use with what you will suggest. C'mon guys don't let me down, gimme some pointers and links!

I'LL TAKE WHATEVER ADVICE YOU CAN GIVE!!

THANKS!

x R i c k