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As far as inexpensive, the cheapest ive seen that will work is show below click link to view
That plugs directly into the microphone port, and is powered by the mac..As far as quality, I wouldnt expect very much.
Now, as far as a small and inexpensive, yet quality device
I would recommend the Olympus ME52w ( shown below ) click here to view
The vast majority of reviews are all five stars.. This is a quality microphone, that plugs into your mac and you can clip it on the top of your screen, or even your shirt, depending on your preference.. Note that neither of these are battery operated.. And they both draw power from the mac.. This has benefits though, as you dont get any signal bleedover from the devices own power source ( which makes your voice less clear )
If you wanted something a bit more expensive, send a reply including a price range, And I will be happy to suggest something that fits..
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