Many of the products I review on my Gadget Navigator\u00a0blog use AA or AAA batteries.\u00a0Most vendors bundle the\u00a0required batteries with their devices.\u00a0But wasting so many batteries has really started to bother me.\n\tLots of my own personal gadgets such as my trusty Logitech Anywhere Mouse MX or Apple Wireless Keyboard also use batteries, and my\u00a0heavy use of these devices means that I replace the\u00a0batteries fairly often. I haven't kept a specific count, but I estimate that I've been using\u00a0half a dozen or more batteries every month or so.\n\tI recently\u00a0started exploring the use of rechargeable nickel-metal hydride (NiMH) batteries. NiMH batteries do not suffer \u201cmemory effect." And they\u00a0looked like an ideal replacement that could generate a return on my investment after just a year or so. Unfortunately, I quickly realized that NiMH batteries suffer from one crucial weakness: They have a very high rate of self-discharge, meaning they discharge when not in use.\n\tMost NiMH batteries can lose more than half of their full charge when kept for a mere two months on the shelf.\u00a0And the\u00a0impact is felt more as their capacity reduces with use or if the batteries are stored at higher temperatures, which is unavoidable in certain regions. This is unacceptable for me, so it was back to alkaline batteries...at least until\u00a0I stumbled upon the eneloop rechargeable batteries.\n\tThe eneloop battery was created in Sanyo Japan by Taishi Maeda in April 2005. Sanyo claims the eneloop batteries retain 75% of their charge after three years, compared with traditional NiMH batteries, most of which would be completely dead in far less time. And\u00a0the lower self-discharge rate makes them ideal for use in low-drain gadgets such as noise-cancelling headphones, wireless presenters, wireless keyboards and wireless mice.\n\tI\u2019ve been using eneloop batteries for more than half a year now,\u00a0and I always have full-charged batteries ready when my current ones run out of juice. I simply swap new ones in and remember to pop the exhausted ones into the charger. In fact, they\u2019re working so well that\u00a0I just bought a\u00a0second pack of eight AA batteries and\u00a0I'm considering buying the \u201cC\u201d- and \u201cD\u201d-size adapters\u00a0for use\u00a0with my daughter\u2019s various battery-powered toys. A pack of eight AA and four AAA batteries with charger is currently available on Amazon for $33.95 (After discount).\n\tHave you used conventional NiMH rechargeable or eneloop batteries? If so, I'd love to hear your experiences.