I just get into one of my easier gears and just try and stand up and sprint. My easier gears aren't very easy though. Standard double with a straight block cassette. (11-21) So when I drop down to my climbing gear 39-16 and I can make it up nearly any hill I have ever ridden.
I walked more climbs when I was on my fixie all the time (47-16) But I haven't walked a hill since I got my Tarmac a few weeks back.