Although I know it does translate to 'free wii' - I still maintain that if someone is looking for information on free wii's - they are not going to type in gratiswii.com - nor are they going to search for 'gratis wii'
In addition, i'd imagine the potential end-users for the concept behind this domain would be people who run those incentivised schemes which give away items in exchange for referals and undertaking of affiliate offers etc. In this case, i'd see them wanting .com/net/info/org etc extensions for freewii, wiifree, wiioffer, clickwii etc etc etc a long time before their wanted list rolled around to gratiswii.com
I still maintain that undeveloped, you're looking at $0-Reg. Perhaps with development and some meaty stats to back it up, you could bring in more money, but that would be based on the website, not the domain itself