i'm pretty much doing straight maths these days...
um. can't really suggest much. though maybe if you're interested in maths/philosophy then consider doing MATH1007, Poetry of the Universe. supposed to be reasonably interesting and not too difficult. i'm doing it this semester as a bludge course.
in first year there's really not a whole lot of choice with chem and maths, you just basically do the main honours streams. bio has a bit more choice, i think. anyway, there'll be plenty of people from each department willing to help you choose - the PhB info session at the beginning of o-week is basically there to help you with all that.