I have used a lot of different dog tags over the years but the Red Dingo dog tags stand out amongst the rest. They come in a variety of colors and patterns that fit just about any personality. Besides looking great they are also extremely durable unlike most other dog tags that show wear after a few months of use. Red Dingo stands behind their products with an incredible warranty; I had one that I used for over a year and the coloring had fallen out (tag was definitely abused) and they replaced it with no questions asked.
http://www.reddingo.com/products/tags/
At Red Dingo we have great looking tags that include free personalised engraving and delivery.
Our tags are typically available in small, medium and large sizes. A small number of cat specific tags are available only in small sizes.