IMO: if you like Canadian paper money take it into a show (bourse) and try to find some note in a series that you like (1954?) and buy a solid radar, or the highest grade rarer note you can find (ie a replacement, or rare signature, etc) in the BOC notes starting from 1935 and to more recent series (unless you like Chartered). Get to know the dealers on the other side of the tables and talk to them, ask for advice, be friendly and show him your note- then talk to business if you trust them.
If you don't care about CDN paper money then the choice is obvious- either sock it away in a safety deposit box (as many Canadians do), spend it or try to get something for it, but don't expect much either way (remember eBay has commissions and listing fees so higher denominations are tough to make a profit on).