This reminded me of a great article about ear plugs:

http://www.slate.com/articles/health_and_science/medical_exa...

The author Nicholson Baker has written about writing with earplugs:

"I’ve always been helped by sensory deprivation. I used to wear earplugs a lot. Sometimes I would write with my eyes closed. But writing in the early morning is different because you haven’t been able to see anything for hours. I would get up and feel my way around. The only help was the moonlight, if it was a moonlit night. You think differently if you can’t see."

http://www.theparisreview.org/interviews/6097/the-art-of-fic...

I tried a similar product, but the silence became unnerving in 10-15 minutes.

I've become quite used to them, though if I can work in a non-distracting environment, I prefer that.

I bought 200 of those and no.. they won't even make me forget the annoying coworker :)