It is pretty amazing when you look at all the under $1000 bikes that cater to small sections of the cycling community -cross, single speed cross, commuter, fixed gear galores etc. Seems like you used to have to build all this up on a frame or mutate and existing bike to get what you want. Now almost any configuration is waiting to ride out of the shop. It wasn't too many years ago that a single speed mountain bike or cross frame would have been custom only.
You want a single speed commuter with mustache bars stock? Redline is waiting.
Generators, fenders, and internally geared hubs? Bianchi's got you. Bianchi aslo has your single speed cross bike (with or without disc brakes even) and pee wee commuter ready as well. Bianchi just keeps pumping them out.
29" rigid single speed mtb? You can try SE Racing or Raleigh and not break a grand. Bianchi also an offering-of course.
You want something that looks like an old beach cruiser but might ride better? Van Dessels waiting with the Counry Road Bob.
I have not mentioned Surly but they have nine highly flexible frames you can build up (8 really since one is a unicycle)
Soft goods kings, Swobo, even have three bike choices for all your urban transport needs.
Nothing will ever match getting a custom bike built just for you or stumbling across a cool old frame and building it up exactly as you envision it, but it is amazing what you can grab off the rack that is so specialized.