As far as good domain names / URLs go, you just can’t beat Big.com, a search engine that has a simple zoom feature to increase the font size of the entire site for users with vision impairment. There’s nothing high-tech or jazzy about this search engine, the important thing is just that you know it exists and that you remember the name (how could you not?) if you ever meet someone who might benefit from it.
There is one other choice, and that is Good50, a project that is famous because it was designed by a high school student for her grandfather. Again, all that it does is Zoom in and out to change the font size for the user. The student, Sunmee Huh, also donates some of the ad revenue to charitable causes. Here is how she is doing so far raising money for Haiti relief, so just by using her site you are also adding to the total.
Adapting search engines for users with disabilities is a wonderful thing. Here is another project, Tazti, a voice activated search engine that is not only fun to use, but is a great application for users with arthritis or other difficulties typing on a keyboard: