How many people don't use Javascript? I bet there are only a handful compared to Javascript users. Almost all popular sites now requires you have Javascript. Take youtube for example.
And you can simply place this in your code in case one of your visitors has JS turned off...
Code:
<noscript>Don't be ridiculous, turn on your Javascript! It won't burn your harddrive. Oh.. and try youtube.com after visiting my site. You'll love it.</noscript>