I like Josephus' suggestion of
MAGIC
But I think we need a challenge or extra incentive:
- Glow in the dark designs (2 color designs, 1 glowy and 1 other
- Rare shirt color (purple, gold, etc)
- Metallic ink designs (1-2 ink colors only, with or without metallic counting)
Also since the 50th derby and the 1 year anniversary of derbies are both coming up, we ought to expect something REALLY cool...