Yes I have one, actually more than one... they are very slick, program in basic, there's a ton of stuff on the web, check out the site... you can do just about ANYTHING with them... I build instruments and use them for the A/D conversion and stuff.. one of the one's I'm working on is a temperature/vaccumn controller with gas inlet that will allow you to run your pump full bore, adjust the picoliters of gas you need to keep a constant pressure, and take the temp off the condensor head... push a button and you get the time/temp/pressure for your fraction...I call it a fraction cutter... $19.00 for the pt temp resistor sensor, I got the absolute vacumn gauge as a sample ( normally $45 ) and the picoliter air valve is about $75.00. LCD screen runs $7-125 depending on how much graphics you want...
Use fuzzy logic to code it, so you don't have to do PID loops and other nasty differentials in your code..
enjoy!
Infinite Radiant Light - THKRA