It appears that after all my screwing around with wireless internet adapters and Norton Utilities, my recent BSOD issues can be traced back to an updated audio driver I installed some time ago. While searching for my Windows 7 DVD, I happened upon the driver DVD that came with my motherboard. For a goof I threw it into the computer and reinstalled the OEM driver. That was last week and I haven't had a BSOD since. I also finally got around to cleaning all the dust out of my machine (the CPU cooler was packed solid), which didn't hurt things either.