Some very cool and interesting results.
I remember my old pal AndyZ (Line 6) used to do this with his clean Pod patches, he turned the Cab OFF.
Start here by using the Acoustic Dream Profile.
https://dl.dropbox.com/u/55111784/Aco…2009-24-02.kipr
You'll notice on this Profile the "Amp" and "Cab" are both OFF.
Leave the Cab OFF.
Press and hold the Amp button, now Browse through various Amp Profiles.
Because the Cab is OFF all the high gain or distorted Profiles will obviously sound like terrible fizz through studio monitors, but when you hit a semi clean or clean Profile the potential is awesome.
Add some Amp Compression, tweak the EQ, lower volume to avoid Output clipping, etc.
Once you have a cool tone switch the Cabinet ON again, listen to the difference with Cab OFF.
I haven't tried it through a powered "FRFR", just through studio monitors.