This is not a wish list, so no past races allowed. It's strictly a "these are the races I want to see before I cash in my chips." All races are fair game, in any discipline. If you really want to see the Unicycle World Championships, write it down. And send pictures if you end up going.
My list:
1. Giro d'Italia
2. Liege Bastogne Liege
3. Cyclocross Worlds (from Belgium or Holland)
4. Tour d' Lombardia
5. Paris - Roubaix (from the Arenberg Forest)