Aha, not a lot :P 20-odd months down the line we're amazingly loved up, dreading the 200-mile distance from September
But at the time of starting AS it was in that 'spending all our time flirting but not actually doing anything' so he seemed to take up all my time AND was in two of my lessons - so a huge distaction until we actually got together. Now we sit and revise - disgustingly cute to be honest
I did AS Chemistry (OCR Salters) and really hated it, found it difficult. Apparently my GCSE course was the easiest one though, I hadn't learnt half of the things I needed to know to start AS, so was busy catching up. A lot of hard work and help from friends (my teacher was awful) and somehow I got an A. This is from getting literally no marks in my first ISA, and failing all end-of-unit tests (and my mock had I not gone through the teachers desk to find the paper beforehand!).
I haven't done the others - the other half does physics and found the A2 really easy (lost two marks on quality of written communication - tut tut!) To be honest, it actually looks quite interesting. No experience at all with biology.
I'd advise against doing Maths and the 3 sciences - it looks a bit one dimensions. Maybe take maths, two sciences, and an essay type subject (just at AS). Geography AS was ridiculous easy, economics is also good (although much harder concepts to grasp).
Hope that helps - let me know if you want to ask anything else!