On the VAG COM front, I bought this one of ebay
VAG COM Car Diagnostic Scanner Fault Code reader
Orange thing for £25, I can't recommend it highly enough for the money...full code reading and resetting. I've used it on my dad's MK4 and it said rear ABS, changed the sensor did the job probs solved.
Also worked fine on my LCR225 and my mates MK4 Golf.. obviusly you can't change parameters like a full VAGCOM but for the money it can't be beaten.