Real Time Effects Software?

So I’ve been downloading some VST amp simulators, and as far as I know, Audacity doesn’t allow me to play through them in real time (correct me if I’m wrong, because I’d be stoked if I was wrong). Is there a (preferably free) program out there that is for this specific purpose? Any help is appreciated, I want to keep using Audacity, but doing this whole trial and error deal with adding the amp effects after recording is a huge pain.

Real time audio effects is a feature request for a future version of Audacity.

Google for “Free VST Host”

So I will add the user’s vote for that.