Bash tricks by Julia Evans
Most of these aren't exclusive to bash; other Bourne-like shells like ksh support these, too.
Instead of Ctrl-R I use the fc built-in for history. It works in both bash & ksh. Using fc -l lists the history, fc -s [number] executes the command again and just fc [number] lets you edit the command with the editor defined in the EDITOR environment variable, or /bin/ed if it's not defined.
good little set of cheats. if you're looking to get expert with bash, this is indispensable too.
also +1 to @vector about `set -o vi`. been using that forever and it's so ingrained now I get a bit initially confused on anyone else's box who doesn't have that set. who uses emacs anyway? lol