My employer does a lot --

Free jersey if you commute both directions X times in a year -- I think the magic number is 14.

$1 per bike commute or car pool; you can opt to donate to a charity instead. They choose a new charity every few months.

Free or subsidized bus pass (don't recall the details)

They'll pay 50% on any biking safety gear (lights, helmet, etc)

A *lot* of indoor bike racks, lots of showers and lockers.

A couple of loaner bikes available for errands near the building, including helmet

A huge breakfast buffet for bike to work day -- actually they usually do the buffet the day after, since a lot of places in Boulder offer free / discounted food on bike to work day

I think that's it ...