05/09
The style will work well if you visit darker sites mostly. The textboxes bg is a transparent image which means the site' color will show through slightly. If you want a permanently set color, just add it right after the word background: in this line: pre, textarea, pre:focus, textarea:focus { background: YOUR COLOR url(......)[if you need help with this, post in my thread linked below, please!]
A bigger shot is here: http://img193.imageshack.us/img193/4921/captureg.png

07/16/09 - code reverted back, seems to work better. Added shadows, slightly lighter bg for textboxes for better visibility. Remember, it's still almost transparent and might look too dark against a dark bg (which is rare in textboxes as they're usually bright white in you face).