Personally I'm fine with the one you use in mountain, You can get it in any shop that sells mountain gears
sorry I didn't manage to find an English web site, but you can have a look at the type I mean all the same

grelobe

Here is a link that might be useful: reading in bed

I can only offer a negative, unfortunately. I have had three different models that work off a battery, and all three seem to use up batteries at the rate of one a week. One came from B&N, another from the Lillian Vernon catalogue and the other was a gift. One that plugs in would be ideal for using to avoid annoying spouse, but would not be portable.

How timely--I nearly posted about the same dilemma last week. One of my children needs one; we've used "headlamps" like Grelobe posted, but this time wanted a plug-in type which clips to the headboard. Cheap was another requirement since said child loves to, um, tinker. Found a gooseneck style at Target but the gooseneck isn't strong enough to hold the lamp up once the light is clipped to the headboard so the gooseneck has to be staked to the headboard like a tomato and it is difficult to move it out of the way of the sleeper who bumped his head on it. Next?

I was looking at book lights at Wal-Mart a few weeks ago and picked up one that looked promising. When I flipped the box over to read the reasons I should choose that particular one, the very first statement listed was: Enjoy your book while sleeping! I actually laughed out loud while the people milling around me backed away very quickly in case I was dangerous.

The book light I've been using for several months is one I purchased from Books-A-Million. The good thing is that it still has the original battery in it even though I've used it often. The bad thing is that the reason it still has the original battery in it is because it uses LED bulbs. That's a bad thing because I find LED lighting very uncomfortable for reading, but some people don't mind it. This particular light is inexpensive, folds flat, and has two brightness settings. I believe that it's this one, which might work for you if you don't mind LED.

I also found this amusing article from Slate about the author's quest for the perfect reading light.

I enjoyed the article from Slate, thanks for posting it! I think we've been through every version of reading light at our house, and my favorite is still the "old" version of the itty bitty book light. The drawback is the price, but after spending money on several cheaper versions, this is still my favorite. It comes in other versions which are less expensive - you can get it with just the battery pack or just the plug in option. I like the light, there isn't a glare, and it can be positioned however you would like.

book light