We used Juno xenon lights under our cabinets. They give off the most wonderful light, but they do warm up quite a bit the longer you leave them on. I found that out the hard way (the chocolate chips in my baking cabinet melted into one solid block!).

I was just thinking last night that I would look for new lights under the cab - my puck lights give off nice bright light but also lots of heat. I would like to find a similar style to #4 but that plug in.

We recently installed the LED strips like #5 (you have to buy extra parts to make them work) and lit our entire counter top for less than the cost of one LED fixture similar to #1. We even had enough extra to put a double strip over our main work area. I even spent a little extra to get a remote control power supply (made for christmas lights) so the lights turn on and off with a key fob remote. We are really delighted with the results and they stay nice and cool.

I have been considering under-cabinet lighting to replace a hideous wall mounted light above my kitchen sink that I chose as a newly home-owning 20 year old. Hideous. It gives off quite a bit of heat, as well- but you know what I've found to be awesome about that? It is an absolute miracle for rising dough and thawing meat!! I may miss it in that respect...

I had bad luck with the LED Puck Lights (#4). I installed them above my oven in my rental. Well, not only did they give off a weird light (cold, dim, cant point them in a specific direction) the adhesive patches that i used to stick them up there gave after only a few weeks. Yup, i had LED lights in my saucepan.

LED is the way to go! Very low energy usage, stays cool, and I'm told the bulbs last practically forever. Can cost a bit more, but worth it.

I chose LEDs for my new under-cabinet lights after experiencing the chocolate-chip meltdown (I feel your pain, kwhit9tl) in kitchens with both halogen and fluorescent lights. They really do heat up your bottom shelves.

We just installed something similar to the Utilitech lights, by GE and from Home Depot. We had them hardwired, so needed some extra pieces, I think they ended up being about $200 for about 12 linear feet of countertop, plus the electrician's time (he was already bringing the kitchen up to code and installing can lights, it was pretty minor in the scheme of things).

I *LOVE* them. So much easier to see what you're doing with undercab lights, and there is no heat at all from the LEDs. We also leave them on when ambient kitchen lighting is appropriate (hard to describe...we have a huge breakfast nook that everybody wants to hang out in, and the kitchen needs at least a little light during those times). They're perfect. Well worth the money.

We moved into a 1954 house whose kitchen was lit only by two fluorescent tubes on the ceiling, one incandescent over the sink, and a three-bulb pendant over the breakfast table. We replaced the fluorescent fixture with something that accommodates CFLs and added a range hood with four halogen lights, but the main lights we use are the under-cabinet LED strips (similar to picture #1). We had an electrician install them, link them, and wire them into a switch on the wall. We had assumed that LED tape would be the way to go, but it would have been 3-4 times as expensive. We did great by linking off-the-shelf lights from Home Depot. I prefer LED and halogen light in the kitchen because it just looks cleaner to me. The LEDs saved me from wanting to replace my countertops -- by distant fluorescent-tube light, the gray cracked-ice Formica looked dingy and drab, but it seems fresh when it's the thing that most of the room's illumination is shining on. It's funny that we agonized over the right ceiling fixture to replace the fluorescent tubes, but now we turn it on maybe once a month, because the LEDs do everything we want.

We have under cabinet lights in our kitchen (it came that way, so I'm not sure what kind they are, but they are wired into the electrical system and work on a switch). We also have some lights on the tops of our cabinets and that is all the light in our kitchen. It works great! Watch out for them heating up though! Like another commenter said, they can get warm enough to warm the bottom shelf of the cabinets over them, so don't put chocolate chips right above the lights (I learned that the hard way).

We found these amazing LED lights which are inexpensive (cheaper than the LED tape lights listed above), SO easy to install and energy efficient. We used them for a bookshelf but they'd work great in a kitchen too.

Details on my blog here: http://www.viewalongtheway.com/2012/01/how-to-install-inexpensive-energy-efficient-under-cabinet-lighting/