Low cost DSP development kit I need  a low cost DSP kit for learning purpose, along with development tools. One main requirement is to process a voice signal (8KHz sampling frequency), with a USB interface.    

Any suggestions? 

Update

A friend of mine suggested that I can use my PC sound card as a DSP- at least for learning basic DSP for sound and speech processing. I would like to know if some body has already experimented with it, and thus can give me some pointers. 

To start with, basic experiments  I will be doing are:

1- Performing sampling of speech or music at different sampling frequency (so the quenstion is can I program the ADC/DAC of the sound card or not?), and play to see how it affects the sound quality

2- Some kind of frequency analysis, using FFT and DFT.

3- Then do some kind of filtering, and then observe the sound quality

4- Deliberately add noise

5- trying to put some phase distortion

6- Using the above to develop a voice recognition system

7- See performance of different type of filters (FIR, IIR)            

My question is if I chose sound  card DSP, will I be able to perform the above tasks, are the software tools available for this purpose ?
You can do a lot for "free" by working with python/numpy.  You can work with .wav files.  Most computers have some kind of sound proceseeing hardware for audio I/O, but you may want to get a sound card if you're computer doesn't already have this.  You can record audio for processing using Windows Sound Recorder.  Numpy has tools for importing and exporting .wav files.

If you really want to learn about DSP coding, get a development Kit from TI or Analog Devices.  These kits include a board with DSP, computer I/O (often via USB) and development tools for generating and debugging code.  Analog Devices seems to have the least expensive development kits.  Try something in the EZ-KIT family from Analog Devices.