If you don't have an fmnu template (see below) and you want to change or add a command key to a menu item, you have to poke around until you find the text of the menu item's name (e.g. "Empty Trash") and then change the byte that is three bytes before the first letter of the item's name to the command key. Maybe an example would help - to use Command-T to "Empty Trash", open fmnu #1255 (ResEdit opens fmnu resources as generic resources unless you have an fmnu template, see below), and change byte number 2C to "T" or $54. Byte number 2C is three bytes before the "E" in "Empty Trash" at byte number 2F. Like most things with ResEdit, this isn't for the faint of heart, and for all I know it may have some disastrous consequences. But it works for me, and I haven't noticed any side effects.
Improve Apple Services with AirPort Base Stations
You can make iChat file transfers, iDisk, and Back to My Mac work better by turning on a setting with Apple AirPort base stations released starting in 2003. Launch AirPort Utility, select your base station, click Manual Setup, choose the Internet view, and click the NAT tab. Check the Enable NAT Port Mapping Protocol (NAT-PMP) box, and click Update. NAT-PMP lets your Mac OS X computer give Apple information to connect back into a network that's otherwise unreachable from the rest of the Internet. This speeds updates and makes connections work better for services run by Apple.