I've been bike commuting for over ten years now. And while Expereince doesn't make you smarter, it does give you opinions
Rambling post follows:
Bikes: I started out on a Sears Special ultra heavy MTB ripoff I "Borrowed from my father (giving him the excuse to buy a real bike) This was the bike I learned to ride on at 14.

After learning the joy of not waiting for the bus, relying on rides and getting around to cool places like the library I managed to break the frame in two places (seperate events), so I upgraded to a Trek 800. 1 Week after buying it with my own money, before I even had a chance to add cool parts it was stolen from an out of sight side of a home while *Locked*. Right next to a little neices window, scary. Being broke I had to ride a rusted garage sale special for a year while i saved up the money for another Trek. Rode the Trek for 5 years before succumbing to various failures. Needing a bike to couumute to work I bought a $70 Toys R Us Special. Not counting tubes I did *Zero* maintence for 3 years. it finally gave up the ghost this winter, replaced it with another Target Special bike. My advice Get a good, cheap bike that you can afford to replace. Riding a name brand bike is like flashing cash at the register, eventually someone else will want it more.
Tips: Pacific brand big box bikes seem to be the best. They're too heavy, made with inferior components and built in China by slave labor but they get me to work *every day*. Only the most desperate want to steal them. My defense, looking cheap. I tie shopping bags on the seatpost, Zip ties "holding" parts on, never wash it, and love nicks and scratches (soemtimes ducttape helps too). Require vee brakes, "spider" cranks (the one that attaches in more than one place) and a front quick release (for those kind souls who might pick you up on a rainy day). If at all possible buy it in the box and put it together yourself. Target will *Not* let you do this. Avoid all suspension, if nothing else is available, get front suspension *Only.*
For reference Pacific makes:
-Pacific
-Murray, their "low end" worst components.
-Mongoose
-Schwinn, their "high end," you may even get a threadless stem
-Some others I forget. They will say Pacific Cycles on the box or frame sticker.
*Avoid* Magna like the deadly plauge it is.
Carried equipment: I am lucky enough to live in the SF Bay Area. so even cold ain't cold and hot doesn't last forever. Rains always come right as I leave for work. That said, I always carry a hunter orange jacket, often worn. everything else I carry in a freebie shoulder pack (that looks it).
I bring road maps of the local area, a super cheap orange plastic poncho, a medium duty yellow poncho, a liter of water, a cup, a *big* wrench (bolt on rear hub), spare AA batts, a handful of zip ties, some Tylonal, can opener (for canned lunches), Fork, hex wrenches, tire levers, lighter. When I get paid a spare tube goes into the bag. One day I'll also have one of those mini pumps and a space blanket maybe even an energy bar. Non-bike related I have my uniform shirt, Lunch, a couple of pens, a book and some tissue. Everything (except the water, cup, jacket, shirt, and wrench) Goes into ziploc bags and sealed with masking tape. It sounds like a lot but except for the shirt and lunch I could carry it all in a sarfari jacket. I use a pocket flashlight on the rare occasion I have to ride in the dark, a multitool for the remainder of my tools. I've lost 2 lights to the "Twist" attack, Don't have the space or cash for a nifty rechargable/generator powered.
Some of my bike stuff doesn't sound like bike stuff, It's "earthquake repellent." Pursuant to Murphys Law, disaster strikes when you're least prepared so by carring a kit I protect the Bay Area from earthquakes.

Well, at least I'll be ready. If I worked around the corner from home I wouldn't bother but the shortest bike/foot route puts me 15 miles and a *Tall* hill from home. If I'm working late (remember Murphy) I'll be more likely to stay out till dawn and then try for it. Warnings about appearing prepared in a diaster noted and planned for.
It seems most bicyclists are more self reliant than the masses. Are you prepared fro your local diasters?
RGB.