Well, in my case the amount of spam didn't matter. It was only used when something needed a site to send a confirmation email to, or as a catch all for spam. So anytime I logged onto it, I was typically looking at the first 10 emails, then laughing at how full the inbox was because it probably had almost 20K emails that I wasn't about to file through and delete.

I had a second account with google that was for things of interest that I didn't want buried under mounds of spam. That has since become pretty much my sole account. Ive got 2 others that I can think of, but I can't recall the last time I logged onto them for anything.