My "The 5" is also my so far unplayed list:
CPC
PV
RCD
RMW
Shinnecock
The first four of these were easy to name. Picking the fifth was tough. I was very tempted to go for an entirely acronymous list (NGLA would have worked well and was in the mix), I'm fascinated by Oakmont, Sand Hills could have been a modern entry but ended up going with Shinny.
Of courses I have played, it's easier:
Royal Dornoch
Royal St Georges
Prestwick
Yale
Ganton
I haven't included a few (Silloth, Deal) that would have been in with a very strong shout because I'm very confident I'll play them again this year.
John M - great to see Silloth in that list. We'll sort that out next year!