Work
Ride bike catch bus/train or walk don't drive
Bring own food/drink
Buy second hand books (in the case of law you can photocopy the 5 page that are actually different between edition 4 and 5)
Use free uni internet
Buy cheaper clothes
Scap money off parents.
As Purple says you have surplus body parts - specifically skin (which will even re-grow), One lung, One kidney, an appendix (you don't really need it), half a liver (it re-grows). In addition to this investigate sperm banks, I havn't looked into it myself but I know that overseas both sperm and blood banks pay donors.