They are pretty big out west. My friends in California freakin love that place. They are sorta like a cross between Compusa (without the shady rebates) and Bestbuy.
I used to go to Fry's regularly when I lived in the SF Bay Area (1997-2001).
Not sure what it's like now, but it was basically a nerd superstore. It was great if you knew exactly what you wanted, but if you didn't, good luck to you. Best Buy is much slicker, with lots of sales personnel. Fry's had more of a warehouse feel.
While they weren't the first to have games on release day (EBGames was always first back then, but now Wal-Mart seems to be just as good), there was no better place for a do-it-yourselfer to find random computer parts like SCSI cables, cases, hard drive enclosures, IDE cards, power supplies, various sizes of fans, etc.