I move offices in March and we're going to be charged to park. I also have a son starting nursery. For these reasons we're going to be giving up our second car and I'll need to get into work under my own steam at least 3 times a week.
The journey is about 5 miles each way and it's mostly fairly busy roads (there's some bits of canal I can use I think).
I've got a decent mountain bike (I think), but I've read conflicting things about other necessities.