Oh you should totally watch some inspirational sports movies!! That always gets me going and excited about doing something active (even if its just walking). I recommend to watch 'Stick it'.
Or how about signing up for a non-gym dance class? Like swing, or salsa or hip-hop. Its a lot of fun.
Or getting off a few stops earlier on the bus, walking up stairs. Everyone says that you dont have to do your excersise all at once, so 10mins here and there everyday is just as effective.
And my personal favorite, putting on some music and dancing crazy for a while haha.