Kerbal Space Program - 51 ton Eve SSTO 

Single stage from Kerbin's surface, to Eve's surface, and back to Kerbin. Mass on the runway is 51.7 tons.
As far as I know, this is the lightest such craft that doesn't use magic wings. Previous record was 57.4 tons by nonRO-tesseract. A bit of lateral thinking here - this can go down to sea level, refuel, and then climb a mountain before refueling again. So technically this can be a sea level Eve SSTO as well.
With the xenon drained this plane becomes pretty hard to control so I just did a water landing. I am impressed at the capabilities of the KSC recovery crew.
Not all gravity assists and ion maneuvers are shown in this video because there were a lot of them and it would be boring.
Music: Zombie Hyperdrive - The Destroyer