Looks like CoolDrives (http://www.cooldrives.com/nasadrenwiou.html) are
the coolest drives indeed... now if only it was $40 cheaper and with a
1394 port :-)
I understand the issues about integrating a power supply (though with
the above implementation it looks like they knew what they were doing),
but through my research I also found out that 1394 support for SATA
enclosures is just as rare, for some reason. Where I work all the
hook-ups are 1394, and everyone calls external HDD's "firewire drives."
Any port besides 1394 on an enclosure would look like a weird beast.
But as you said, every computer with 1394 has USB...

So all things considered, I'll probably go with an eSATA+USB solution.
What do you think about these candidates?

VANTEC Nexstar3 NST-360SU-BL (a.k.a. Welland ME-740J)
http://www.vantecusa.com/p_nst360su_bl.html
http://www.newegg.com/Product/Produc...82E16817392002
http://www.welland.com.tw/html/enclosure/x40.html
$30 in Newegg, bracket included, supports up to 750GB

Rosewill RX353-S
http://www.rosewill.com/Product/prod...?productId=502
http://www.newegg.com/Product/Produc...82E16817173040
Internal fan (reviews are ambivalent though), compact power adapter,
bracket included; up to 500GB.

The OKGEAR OK350AU2S1-K looks like any other enclosure, except that it
claims to support up to 1TB.
http://www.newegg.com/Product/Produc...82E16817348016

Happy holidays!