Aside from a ridiculous, flashy SVI race gun because I'll never be able to afford one?
Two come to mind:
Colt Python .357 with combat grips - because they don't make them any more and the prices for used ones are ridiculous.
Taurus Judge - I realise they make a longer barreled version for Canada, but it's pointless if I can only ever use it at a range.
Actually, not being allowed to take a pistol up to my cottage to plink (even a .22!) is, to me, a huge deterrent to buying one. Ruins a lot of the potential fun, and adds a lot of cost in terms of range membership. Nice try, CFO, but I'm still going to buy a few.