I've had only 2 hiccups with this site since I've been visiting here & I'm definitely not complaining.
My ISP is a pain though, I've given up logging onto his poxy proxy. Keeps turning it's toes up. Maybe, if some are logging on via a proxy server, if you log on directly to the net may cure some speed & reliability problems.
But I certainly agree with all that has been said re: defrag, spyware, cookies etc & cleaning out your cache regularly.
Taking off and flying are optional. Landing is mandatory