The list is long. The guys who helped me with the frequencies on my band's demo when I didn't have anything remotely accurate for monitoring (Glenn, Unavailable). Also, the guys who I worked with on the Dio Tribute Skinny Viking (I still owe you a Children of the Sea vocal recording), Sarj, guitarguru777, RickPart, and anybody else that I forgot to mention. Aside from that, the information I've gotten from reading what tons of you guys have written has been beneficial to me...even though I haven't been doing any serious recording at all lately...
...and Philsbeard.