spring spontaneity

So I've decided it's much too gorgeous to stay inside and I owe myself a trip to the city to get some glimpses of the Japanese Tea Garden in full bloom & walk around Golden Gate Park. I'd like to hang out in a cafe and do some work on my laptop.

Anyone know the best cafes with Wifi in and around the Haight/Upper Haight or other suggestions for things to do in SF today?

x-posted to SF Bay Area