It doesn't take much awareness to realize that bicycle commuting, and bike use in general, is on the rise. There are articles in local papers, growing numbers of blogs, and increasing accomodation for bikes in street layout. Heck, just go outside and look around. The three main reasons seem to be, in no particular order, 1) the high price of gas, 2) health concerns, and 3) environmental concerns.
Now I know most people think "technology" means the ability to communicate wirelessly while watching high-definition video of the latest world event and listening to downloaded music. But believe it or not, there's still technology that's purely mechanical, and there's a lot of interesting innovation going on there.
Bicycles are among the notable beneficiaries of this mechanical innovation. There are two technologies in particular that are very promising for commuters and heavy-duty bicyclists: internal gear hubs and shaft drives.
The shaft-drive replaces the greasy bicycle chain, with it's cogs, cassettes and derailleurs, with a neat little tube housing that extends from the pedal crank to the rear hub. Inside, protected from the elements and road conditions, are the drive shaft and bevel gears. The principle is simple: you work the pedals, which turns the shaft, which turns a gear at the rear hub. That would be enough to make a very robust single speed bike.
For multiple speeds, though, you can't use a derailleur that pushes the chain back and forth among smaller and larger gears. Instead, you can use one of the internal gear hubs like those from Shimano, SRAM and Rohloff. Again, all the mechanisms are fully enclosed in housings that retain the grease, and keep out road dirt and other crud.
Dedicated recreational bicyclists are used to doing a certain amount of maintenance to keep their bikes in prime performing condition, and fortunately, bikes are pretty simple, easy-to-understand machines. But for commuters, who just want to hop on and pedal to where they're going, the low-maintenance aspects of these enclosed mechanism, the shaft drive and the gear hub, are a huge boon.