ALT+SHIFT in combination with [size=24px]+[/size] or [size=24px]-[/size] , will change the layer blending mode or if a tool is selected that has a blending mode, it will change that particular blending mode instead.

Blinky2004

And...
In PS7 (haven't seen this work in 6) if you select the text in the blend mode menu so it's highlighted, you can use just the up'n'down arrow keys to scroll through the modes.

NOTE: not 100% sure that this isn't just a WinXP ability. Take it with a grain of salt.

UglyKaterpillar

Yep, version 6 lets you scroll using up & down arrows. 5.5 doesn't allow it though. Oh, but both computers I'm using have XP so...

Scrolling through blending modes with the cursor keys has always worked for me in both PS6 and 7 using Win2k.

Blinky2004

aaa ok cool then... good stuff to know. Thanks!

gymmie

Works on Mac OS X, PS 6 too