In poker, a game played with a no limitbetting structure allows any player to raise any amount of his stake at any time (subject to the table stakes rules and any other rules about raising).
... 1991 Leonard Cohen
1992 Ian and Sylvia[?]
1993 Anne Murray
1994 Rush
1995 Buffy Sainte-Marie[?]
1996 David Clayton-Thomas[?]
1996 Denny Doherty[?]
1996 ...