Tone Mine lets you use music and sound effects on the site to create your own ringtone. You can then email and/or post the url of your creation on a blog or online journal.
There are actually quite a few ringtone makers out there. Many of them allow you to mix music that is inappropriate for classroom use. I took a quick look around ToneMine and didn’t see anything like that, though I have to admit I didn’t spend much time on the site.
However, what really makes this application useful to English Language Learners is the sound effects. One of the ways I teach vocabulary in the classroom is by using sound effects (animal sounds, etc.). You can integrate a lot of these kinds of sounds into your ringtone with ToneMine, and they’re labeled. It’s a good vocabulary-building exercise.
I’ve placed the link on my website under Student Songs.