Well, on most Mac laptops, you can use SideTrack and tweak the "tap filtering" options. In particular, I've found that the combination of the "Ignore trackpad while typing" with a 500ms or so timeout and "Allow sufficient finger motion to bypass filter" options has gotten rid of all accidental taps while still allowing me to use the touchpad with my thumb while I'm typing.

I know the Synaptics drivers for Windows had similar features back when I used them, though not quite as flexible. Maybe they do now, if they still exist / are used on modern PC touchpads.