The more recognisable your bike, the less chance of it getting stolen. The newer, fancier it is, the more chances of coming out one morning to find it is gone forever. LOCK it! Get a lock, and not just the cheapest, but the big hard tough ones. The people stealing your bike are professionals so make it as difficult as you can. Make sure you have the back lock on your bike, and then lock the front wheel and your bike to a bike stand. There is nothing more frustrating that coming out one morning late for work to find the bike is gone!