I've had undercabinet lighting in my kitchens for many years.  Earlier systems used small florescent bulbs that were bulky and somewhat expensive if you needed more than one.  Then, halogen lighting started to appear, but they were low-voltage systems and required an external transformer, an inconvenience and unreliable.  Then, a big-box home improvement store offered individual, small, round, lights with each operating independently, i.e., no transformer, running directly from 120 vac.  Each light has its own ac plug which is somewhat inconvenient when you have 6 or 8 or more to plug in.  What I do is to cut the plug off and connect them all together in one or more electrical boxes mounted under the cabinet.  This approach also allows you to install a single dimmer to adjust the brightnest of all. Very nice effect and reduces the heat coming off the lamps.  I once did this during a major kitchen upgrade which was pretty easy.  But, recently, I did this to an existing kitchen.  This required making holes in the backsplash and patching them later, or, in my case taking this opportunity to add a tile backspash which covered the patched holes. The only downside to using these halogen lamps is that replacements at the big-box store are quite expensive - $4 to $5.  I haven't had to replace too many but was pleased to find this much lower cost source of lamps at Amazon.  I only have one in service now so I don't have any feel for their operational life vs the life of a big box lamp.