Modnation racers is having a whole double XP week in honor of Valentines day as well a free DLC creation to drive around in. They have a car named the Lovebug which looks like a swan from a tunnel-o-love.
I haven’t played a whole lot of Modnation racers, but the bit that I did play was fun. The only thing that ultimately drove me away were the excruciatingly long load times for getting into races or creating races. Still it looks like Modnation still has a decent community and cool tracks are getting made, just goes to show that any game with really good creation tools and sharing options can thrive.