I believe the title is self-explanatory. Any way to convert MIDI files to WAV files?

I understand that MIDIs aren't real sound files - just commands sent to a PC synth - but there's gotta be a way somehow. I read somewhere that you can feed the MIDI to an external synth, and have the external synth play it into a wave file on the computer, but I don't have that...

Any insights?

edit: A friend just told me about Cubase, which apparently performs the said task. Any information on this?