General Knoppix support for those who've read the FAQ at the Wiki
Grandstream GS-HT802 2 Port Analog Telephone Adapter VoIP Phone & Device, Black
$32.00
MagicJack - HOME VoIP Telephone Adapter 12 Months of Service - Black New Sealed
$39.99
Nortel Avaya 1140E XNTYS05BCE6 PoE VOIP IP Desk Phone Telephone Bluetooth New
$39.99
Cisco CP-8841 VoIP Phone - Black
$20.00
MagicJack - HOME VoIP Telephone Adapter 12 Months of Service - Black New Sealed
$39.99
Polycom VVX 301 6-line Desktop VOIP IP Phone 2200-48300-019 *NEW*
$24.99
Cisco/Linksys SPA2102 VoIP Phone Adapter Router 2FXS (Unlocked)
$16.99
Mitel ShoreTel 480G Black 8 Line VoIP Business Phones IP480G
$29.99
REF A-STOCK - Polycom 2200-48450-025 VVX 411 IP VOIP POE Gigabit Telephone
$38.68
UBIQUITI UVP Executive Unifi VoIP Phone - 7" HD touchscreen - Unlocked #003
$120.00