At the moment our band has a very limited PA system so there are times when it's not always easy to hear myself on stage. However, having this new Carl Martin Quattro got me thinking..... It has a dual mono output and at the moment I just use one of them to go to my own amp's effects return but presumably I could use the other one to go to a small amp that I could use as a monitor. I'm guessing it couldn't just be any old amp that doesn't have an effects loop because then it would be going through another preamp or does that not matter if I'm just using it for monitoring purposes? Any ideas on what I could use that I could pick up cheaply secondhand?
Gibson Les Paul Studio with Catswhiskers pickups
PRS SE 'Floyd' Custom 24 with Creamery pickups
Fender Standard Stratocaster with DiMarzio pickups
Takamine GN30
BluGuitar AMP1
Look for a powered wedge used, they pop up a lot. Cathbard will probably drop by and give you some specific brands and models, hes into this stuff.
I don't give a shit if you listen to me or not
The band I'm playing in right now has a wireless in ear monitor system. It works great. I can hear everyone perfectly while moving anywhere around the stage, and the shure in ears that I have also block out all background noice, protecting my ears, and allowing me to focus more on the music. No more ringing ears when I get off of the stage!!

I know its a little pricer option, but well worth it. The sure system we have was about $400, and my in ears were aout $100. You can find cheaper products then that though. The in ears are great for recording, and just listen to music as well. They're great at blocking out annoying cyring babies on long flights as well

I thought I'd just throw that out there.
PRS Custom 24
Gibson Les Paul 60's Tribute
85' MIJ Strat
97' Snakepit Les Paul
LP Traditional 1960 Zebra
MIJ Tele
MIA Strat

Silver Jubilee 2525
Peavey Ultra 112
Jet City JCA50H
66' Bassman
Pink Paisley Princeton RV
74' Vibro Champ