Check out the Gleis 7 pass - available if you're under 26 IIRC, only 100 CHF more than the half-fare card but also gives you free travel after 7pm (see link in fact sheet linked above). Also, try using click and rial on the SBB website - you can get discount tickets on certain routes at certain times, and they are bookable up to 2 days in advance. The day-passes can work out to be a good deal for doing a lot of travelling in one day, if starting after 9am or on weekends, they are only 56 CHF I believe, but can be even less if bought through your local commune (see this thread), and are often on discount throughout November (see this thread).