100+ emails a week in my primary inbox that are from people signing up to random stuff in my name, basically any/every service you can imagine where I don't already have my own account (large social networks and sites in countries other than me own, online shopping sites, etc).
The other interesting thing is I seem to get a LOT of email for addresses that "almost" match mine, as though Gmail is doing fuzzy-search for addresses? Eg lets say my email is "david@gmail.com", I get dozens of emails a week for "david.17@gmail.com" and "davidab@gmail.com" and stuff like that. I can't explain this one, and everyone I bring it up with says it shouldn't be possible.
It's gotten to the point where I've created a more normal fullname@gmail.com and then do some filters/forwarding on the old one for the more important emails, then just check the old one every couple weeks to see if I missed anything, because it's just not usable anymore with notifications on.