I am Mohan Rao . More than 3 1/2 years working on asterisk .
I have seen many replies for the low cost asterisk USB fxs adaptor.
So here is one more.
I have developed USB fxs Adaptor for Asterisk . Also written the Drive for it . Working efficiently . I am plainning to upload it . By the time If any body is intrested drop me a mail.
Also few future plans :- hardware/ software will include FXS/FXO PCI Device .