I don't find too many Flash games to be very addicting or visually interesting these days, so when I do, I feel it's worth mentioning. Victorian BMX is a nice blend of contradictions. You play the Grim Reaper riding through an obstacle course beheading English citizens along the way. Truly inspired! My only gripe is that the physics engine tends to be a little unpredictable when it comes to very jagged terrain. I still haven't managed to beat the final location.