Outfitting a commuter

[Owlie]

I'm picking up an old rigid mid-90's mountain bike (a Giant Iguana) for use as a commuter and beater bike on Tuesday, and I'll be picking up all the stuff I need for it after that.
Okay, what do I need? Since it's a commuter/beater, I don't want to put anything super nice on it, but I want the stuff to last. (Oh, and I'll be in desert-land for most of my time with this bike, so I doubt I'll need fenders.) I'll be using it to commute to school, possibly light grocery runs, study breaks at the coffee place, that sort of thing.

Given: New saddle, probably new chain.

Must-haves: Rack (it does have eyelets), lights (suggestions for bright-but-inexpensive ones?), flat kit for this bike (how to stow it?)

Probably: Second bottle cage, wheel reflectors

Maybe: Pannier(s) of some kind, very basic computer (that I'll store with me).

Any suggestions? Other stuff I should get that I haven't thought of.

[Irulan]

Mirror

[OakLeaf]

I use the horn on my commuter all the time because I wind up on a lot of shared use paths. I'm guessing a campus situation would be similar. Usual order of notification is bell (which came with the bike, I wouldn't bother with something no one can hear when there's a single car on the same block), spoken warning, horn, wish I had an air horn when they continue to weave all over ...

[shootingstar]

You probably have it --water resistant jacket/pants.

Otherwise you're good.

[Crankin]

No need for those in Tucson... unless Owlie plans on riding in the monsoons next month.

[colorisnt]

I think you pretty much got it

If you want a pannier, get a big grocery-style pannier. If you want to commute in the rain, invest in something waterproof (doesn't seem like that's a big problem for you haha). I have determined that our trail is simply not safe for me to take the road bike in the rain so I gave up on it. I have a cheap bag. I paid about $30.00 for it and it's plenty big but not too big for my 47 cm bike. I also have a trunk bag (waterproof!) just in case it rains. I haul my books, computer, etc with me to campus along with a change of clothes no problem. I hate hate hate backpacks so I carry the bag instead. If you have a backpack, YMMV. I just hate having to carry one with me around campus.