I too have started gardening and have found that by doing so I gain:
Access to the freshest, most delicious, carbon footprint free, organic produce. I too have broken even on costs meaning from now on its all free.
Membership in a community of other gardeners worldwide
Something fun to look at as I drink my morning coffee
A deeper and more meaningful connection to my food
The feeling of badassity that comes with incremental steps toward self sufficiency
Health, due to the fact that I always have fresh veg coming up as fast as I can eat it, making grocery stores and the temptations that come with them a rare occasion. I have become partially vegetarian simply because it is a drag to have to go buy meat all the time.
I use Larry Hall's Rain Gutter Grow System and if you're not familiar, check him out on youtube. Mindblowing results, and I am able to do it as a renter!