if you have vmoda headphones the proboom is certainly very convenient, otherwise it doesnt work all that well with other headphones.
the modmic is the best of the add on mics which would work with any headphone easily.
for on-the-cheap you can diy a fix like this http
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/imgur.com/gallery/bKU4H/
there are some other mics similar to the modmic (mainly the moovemic which is nowhere near as good) or clip ons like the zalman (again, which is not as good).