I have to agree with a couple of others that suggested the
Innokin iTaste MVP. Just picked up one of these a couple of days ago. The built-in proprietary 2600 mah rechargeable battery has been said to last up to three days on one charge, can charge your cell phone if necessary, and fits easily in a shirt or pants pocket. Variable voltage up to 5 volts. No built-in atomizer meter in this.
http://altsmoke.com/starterkit/innokin-mvp/innokin-mvp-itaste-kit.html

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Bottom feeders seem to be becoming more popular. I recently got a
Vapage VMod-XL. The AW 18650 2000 mah IMR battery lasts me nearly 2 days, and the 9 ml juice bottle lasts me 3. The pure unadulterated flavor of a drip atty and the convenience of a tank. Easily fits in any pocket. Doesn't leak. What's not to like about this?
Also available in an even smaller model (VMod 2.0) that uses a 14500 battery and 4 ml juice bottle.
http://www.vapage.com/V_MOD_s/173.htm#


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For extreme stealth and something that's not going to break the bank, the $16
Smoktech Gripper (mechanical) is tough to beat. Takes an 18350 battery that should last most folks several hours or more. If you plan on using something other than an XL length cartomizer with this, be sure to grab the gripper extender for a few bucks to be able to use a clearomizer or cartotank.
http://www.gotvapes.com/index.php?main_page=product_info&cPath=104_273_235&products_id=1309




