Some quick tips for better productivity when developing Drupal core:

• Alias your editor to e. If you use a GUI editor see if it comes with a command-line shortcut to use. TextMate by default has mate. Not nearly short enough ;).
• Set up a d command to perform diffs. I use the following: #!/bin/bash
cvs diff -u -N -F^f . | grep -v -e ^\? > $1.patch
e $1.patch This opens up my editor afterwards so I can review the patch before submitting. The grep strips out unnecessary junk (unknown files).
• Set up a p command to apply patches. I use the following: #!/bin/bash
wget -O - $1 | patch -p0 This will take a patch URL and apply it locally.

Anyone else have anymore ideas?