Bah don´t listen to Simon he just has phobia of any sports that involving some movement.
Well I haven´t tried badminton so i can´t really say something about it.
Basketball is quite fun although since the turn out is not that big we have to run ALOT so it would be great for more ppl to come along so we don´t have to run so much. You see Simon when you say things like that about basketball you shouldnt be surprised than not a single girl turns up (understandable

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Volleyball is quite a good sport and I definetely recommend, it doesn´t require as much running, its pretty safe and its great fun!! Additionally it´s a non-contact sport which means you shouldnt be afraid of discoordinated ppl crashing into you (hmm... then again..) You may get some sore wrists but once you get the hang of the techniques that won´t happen again. Both guys and girls have turned out so far so dont worry you won´t be the only boy/girl there.
As for suggestions i have a couple:
Handball - It´s a very cool sport that not many ppl have tried so it would be good fun to try it out
Football - we never tried this... I´m a crappy player but it would be cool to do it once in a while
Netball - kinda like basketball but different... im not sure about rules...
Ultimate frisbee - then again something different that i´m not sure about the rules but we can check anyway
Let me know what you think.