Thanks for all of your input. Hog - by "monitors," I was referring to powered speakers. Some of them have multiple inputs and can mix the signals from both, so I could have both my computer and black box plugged into them at once. I think I am going to try on some headphones and see how that feels.
Guitars: MIM Fender FSR Limited Edition Stratocaster with direct mount pickups, Schecter C-1 Plus, SX SST57 Powder Blue, Alvarez RD8 Accoustic
Amps: Line6 Spidervalve 112
Effects: Digitech Bad Monkey, Danelectro Cool Cat Chorus, GFS Delay, GFS Tuner, Behringer HB01 wah, Line6 Toneport GX, GuitarRig 3