put it on ebay, and sell individal copies for say 50 quid each.

for each auction, have 10 available. 10 people buy it, you got 500 squid, and then you can do it again.

you could put it in an excel file with password protected sheet to make it a little bit difficult for the buyers to distribute to their mates. and anyway, if i bought it for 50 quid, i wouldn't want anyone else having it for nothing, they can buy their own, would be worth it for that price.