moopie - plugmold. Tamper-proof is necessary for most codes, and angled plugmold is probably the best option. Here's one option: http://tasklighting.com/ap-tr-series/

Some of us have used an angled wood strip to attach regular plugmold to as well.

Either option works.

Here is a link that might be useful: Task Lighting Tamper Resistant Plugmold

Plugmold is legal, but the outlets do have to be tamper-resistant. Keep in mind that if you put plugmold under your upper cabinets, and keep any small appliances plugged in, you will always see the dangling cords. I personally prefer to see outlets and hide the cords, but YMMV.

To Sjhockeyfan's point, many people opt for a mix of plug mold and a couple of outlets placed strategically for coffee maker or mixer. Or, don't get plug mold, but make sure to install receptacles in your backsplash horizontally, and as close to the counter as local Code will allow. They will barely show with that placement.

I went with plugmold with angled wood
I can post when on the computer.
I chickened out and put in some outlets in the BS (3 total)
In retrospect, I would have left only one in the L corner
Had I known about optical garbage disposal, I would have gotten rid of the GD switch/outlet. Also on the baking wall, I could have lived without the UC light switch/outlet.
No big deal as I have a few counter items to blocking some of them.

Yes, for sure consider if you keep things plugged in all the time. If you do keep things on the counter and plugged in all the time, you'll see the "pigtails". We eliminated small appliances on our counters (they reside in a tall cabinet in an appliance garage), but we did retain one single standard plug - we keep a landline with a cordless phone plugged in there. It's back in a corner area hiding so that even if we do wind up getting rid of the landline some day, the electrical outlet won't be terribly obvious.

We did the horizontal placement because we initially thought that we would have our tile running horizontal...but we outsmarted ourselves and ran it vertical. So now we have a horizontal plug and vertical tiles! Just can't win! haha