I always carried a torch at work, and still have one in my pocket when doing mechanical work. And I'm a sucker for gadgets, so have bought a lot of torches over the last 12years My recommendation until recently was simple: Fenix LD10. They've since replaced it with a very similar tool, the LD09. They cost about £30, which sounds a lot, but is really good value.
My reasons for liking these: it's a sensible size using a single AA battery, the 3 output levels are sensible and easily switched between, it uses a tailmounted click-switch, it can be stood on its tail to light a room, it's extremely robust, the battery life is reasonable - I used mine all the time and got over a fortnight out of each battery - in high power mode it has a pretty good range and throw which makes it usable for searching fields, and the price is OK. I tried, and still have others, but for various reasons this is the only one I would replace. I don't find the potential higher output of a CR123 battery worth the massive extra cost as they lasted no longer than AA batteries; the smaller rechargeable torches tend to be a bit bigger if the controller is internal, and if using it as a tool an external charger(other than a micro-USB lead) is unacceptable; side mounted switches are easily switched on accidentally; twisting the end cap of a smooth torch with oily fingers is obviously a bad idea. The LD10 has the most important characteristic for good design; it just works with no niggles. One complaint I have of this sort of torch is that they are all anodised black which is a stupid idea for a light source; I would happily buy another if they made one in a bright colour or silver. This is the only thing that Maglites have in their favour and it isn't enough for me to buy another.
I did have one like RobG pictured and wasn't impressed: it's bright but the throw/spread/colour isn't particularly useful, it's bulky, the charger isn't reliable and the lamp broke quickly. I went back to using the torch in my pocket.
As for batteries, buy them in bulk. I bought 50 AA Procell for about £15 over a year ago, have used them in my torches and other stuff and still have half of them left.