This is a great inexpensive gift for any teacher. In my preschool classroom, I use hand sanitizer all the time. In fact I have the extra, extra large bottle of it. All you have to do is find the clear bottles of hand sanitizer and tear off the labels. You can get the sticky stuff of with some Goo-Be-Gone.
For the decorating of it, I used rub on stickers and some ribbon that I had lying around in my scrapbook stuff. You could use whatever you'd like. You could also add a tag of some sorts to it also. Here's the finished product. Easy, fun, inexpensive, and a gift that any teacher would like.