The fastest way to a $250 Brick.
Some legal mumbo-jumbo to add to the discussion.
Mod-Chips serve 2 main purposes in consoles (i.e. the Wii)
1. Allowing the playing of Homebrew Software (This is legal in the US and companies may oppose it, but have no legal grounds to do so)
2. Playing burnt copies of ROMs. Two sub-points on this
A. Making archival copies of software you own is LEGAL and cannot be prevented under US Federal Law. Companies that try to sue/prevent archival copying open themselves to lawsuits under the Fair Use statutes in Copyright law. This can even invalidate a copyright.
B. Copying software you have not purchased. This is ILLEGAL, and carries penalties of $10,000 and Five years in Federal Prison in the USA. DON'T DO IT! Seriously, saving $50 on Galaxy is not worth becoming Big Bubba's special friend for half a decade.