Try local ISP's or other call centre jobs. Most run 24/7 these days and you could do either the evening or night shifts along with weekend shifts. Lots of these positions call for Uni students as they know they need their shifts.
Console operator work also is an option, as once again it is shift work, as is a sales assistant in a 24 hour convenience store.
Other options include bar and waiting work, if you have a few spare dollars and a day or two before you start uni, get your RSA (responsible service of alcohol) badge from TAFE which will give you the edge over the positions when applying.