Hello all I'm Pete, I have only recently started Geohashing but have been a long time xkcd reader. This page was copied from Robyn who looks to have a pretty complete user page.
Things that have thwarted me
All Geohashes Attempted
Checklist of achievements to get
first, time traveller, endurance, no batteries, geoflashing, underground, underwater, golf, pub, hash collision, freeway, birthday, picnic, sex, snowman, twister, phonebooth, hopper, restricted. McGyver, circus, and most everything else that has been made up.