Worked the gate and check-in for Virgin-Atlantic, as well as ticketing and ramp for ExpessJet...
I also did it as a leg-up - of course, it didn't end up working out how I had planned, but I wouldn't have changed a thing. I don't know, maybe I'm just a major Pilot-nerd, but I absolutely loved going to work for both VA and XJet...the only job I have ever enjoyed more is now as a Pilot.
One recommendation: there are a lot of sick people out there. I made the mistake of not hiding my desire to become a Pilot. People can get jealous and it only makes for an antagonistic working relationship. It is a great job, and the opportunity to network is endless (countless offers to walk-in my resume while I was pushing a crew back LoL). Just be smart about it!