There has been a moe themepack for Windows 7 floating around featuring various Windows sound effects.
The theme originates from a limited edition of Windows 7 sold in Japan. This pack includes 3 wallpapers, and most of the sound effects as voiced by Mizuki Nana (水樹奈々). More information about the pack itself in Wikipedia, and on Akiba blog.
Here’s preview of all the sounds on Youtube. This was mirrored from NicoNico:
Well I tried it out for a while now, but then today realized that the one being distributed actually has a mistake in it. The person who packaged the themepack swapped the USB connect and disconnect sounds. To fix this, you can either modify your downloaded themepack.
If you want a manual fix, you have to do is swap the filenames of ‘device disconnect.wav’ and ‘device connect.wav’ under the themepack’s folder under your local user folder.
After the fix:
Device (USB) Disconnnect is supposed to be:
ぁ、つながったよ (a, tsunagatta yo) -> a, it’s connected
Device (USB) Connnect is supposed to be:
ヌいても大丈夫だよ (nuite mo daijoubu da yo) -> it’s okay to disconnect
If this link does expire, you can most likely just download it from a Google search for "nanami themepack"