>Could someone tell me what HylaFAX provides over FlexFAX?

It's obvious, of course - the letter "h" is ahead in the alphabet of "f" :-)

But seriously, it's really the same software, just a new name (turns out
FlexFAX was a registered trademark).

Off the top of my head -

- Greatly improved queueing system.  There's now a central queueing process
  that farms jobs out to individual modems more efficiently (which only really
  matters if you have more than one fax modem)

- Support for time-of-day restrictions and priority-based queueing.

- Support for Caller-ID and distinctive ring (if the modem supports it).

- Preliminary support for alphanumeric pagers via the IXO/TAP protocol.

All in all, it's a hell of a lot better the the last beta release!

--Ken