Wireless Microphone Recommendations

I have received a couple of comments from people who would love to attend my presentations but cannot due to the distance factor. I have also been asked on a couple of occasions to Camtasia the presentations so that I can make them available for download after the fact. I am going to attempt to do this with my presentation next week. Before I can accomplish this, I need to request recommendations from people about good wireless microphones I can use with my laptop. Obviously, at presentations I do a bit of walking around combined with sitting at the computer hammering out code. I want to make sure the presentations continue to appear smooth and seamless for the people attending in person. I also want to ensure that people who cannot be there receive all of the spoken dialogue as well as the screen recordings. Any feedback on good wireless microphone solutions would be appreciated.