I seem to remember that you're an expert on the subject and if possible I'd like to have your recommendation. I currently use the classic pen style (I believe it's 801) and although I'm happy with it as far as it goes, I keep seeing (or hearing about) improved devices. (I believe you said you'd tried a lot of them.)
With the 801 I haven't smoked since July 2007 and I'm actually mildly disgusted by the smell of tobacco smoke so that's good. The downside healthwise is that I've put on a lot of weight. I've also saved a ton of money even with the unreliability and high cost of the physical parts. I suppose I have 20+ batteries that I cycle through, change atomizers about every three months, and (this one's not expensive) have half a dozen bottles of juice open at any one time. My biggest complaint is the inability to produce "a good head of steam" especially after I've dropped some juice into the tip. I'd consider it a "good head" if I could surround myself with as much vapor as a normal cigarette would produce as smoke.
I don't want to run this off my PC nor connect it to the 120V house current (except for re-charging). Looks-wise I'd be very happy if it resembled an asthma inhalant (wouldn't that be a blast: how could anyone object to you treating your breathing problems wherever you were) and it could be the size and shape of a pack of cigarettes (I have an empty shirt pocket which used to be used for this purpose) so a 12V battery wouldn't be out of the question. It certainly doesn't have to resemble a cigarette.
Any suggestions?