I have seen that Intel has a tool that gives Trim support to older OSes running on Intel SSD's.
We are rolling with Crucial SSD's, and everything is XP.
Is there a utility or trick?
I take it back. It looks like Intel has a utility, as you pointed out.
And apparently Crucial supports user-managed garbage collection on XP and Vista too. I found this information on this page:
The C300 supports garbage collection, which means the drive collects old blocks while it is idle.