Dragon naturally Speaking??
Apple Macs have some sort of program installed I think. i listen?? maybe??
Windows 7 has something installed already also.
more info-
http://www.google.com/#hl=en&q=voice...06bc2a5dba00d4
**Important also**
a good mic
a good quality sound card
If you get a good Mic and still have troubles with the program recognizing your words - then upgrade your sound card.