Show last 3 posts instead of 1 on index?

[MisterMan]

Sorry if I've missed the answer elsewhere, but have searched until I'm blue in the face.

At present, I have my forum set up with a number of categories, each with one thread.

The index shows each category, plus its respective thread, plus the last post for that thread.

Is it possible within either the regular options menus (tried, but can't find a way) or by some simple customisation (stress on simple) to have the index page set up so that, say, the last 2 or 3 posts per thread are shown instead of just the current single post?

Many thanks