If you haven't already, see if the Apple chat people can walk you through some stuff, poke around a bit, see where you can kill live processes that are hogs and find the reason they started. That's what I used to do on my Windows boxes, not entirely fluent with my Macs yet lol.
If you have had no luck with them, see if any local repair shops have ideas they can recommend over the phone. Phone calls are cheap, and sometimes you get lucky with a fix. If you offer some sort of payment for an extended phone call/webcam chat, that's probably not a bad idea if you'd rather not leave the computer in the shop for a few days. If I have anything that needs "repair" of some sort pop up with anything non-mac (that's all I own under a warranty), I'm seeing who will do a call of some sort to help me. Bonus nachos for the people who provide an email with links ?
Hey, a lot is different nowadays; get friggin creative! See who is happy to do more without physically doing the work that costs them money to do! Diagnosing some computer stuff can cost ya money when you scale it out... try to cut their corners for them, and get some extra service that is a win/win. Someone will jump at the chance. Worst case, you wasted a few hours and it costs you your usual phone bill ?
