General Knoppix support for those who've read the FAQ at the Wiki
Grandstream GS-GXP2170 VoIP Phone & Device 4.3" Color-Screen LCD Gigabit Ports
$45.53
Genuine Desktop 8 Line Gigabit VoIP Phone System Mitel IP480G PN 630-3481-01
$89.99
Grandstream GS-HT802 2 Port Analog Telephone Adapter VoIP Phone & Device, Black
$29.99
Polycom VVX 411 IP VOIP POE Gigabit Telephone ONSIP GOOGLE VOICE ZOOM MEETING
$24.00
Cisco CP-7945G VOIP Phone With Stand & Handset Business IP Phone 7945
$3.00
Grandstream GS-HT802 2 Port Analog Telephone Adapter VoIP Phone & Device, Black
$32.00
Polycom VVX 411 IP VOIP POE Gigabit Telephone [L/N] BUSINESS OFFICE RECEPTION
$24.00
Cisco/Linksys SPA2102 VoIP Phone Adapter Router 2FXS (Unlocked)
$16.99
Yealink T54W IP Phone, 16 VoIP Accounts. 4.3-Inch Color Display - Black
$99.99
Polycom VVX300 VoIP IP Phone & Stand Warranty Reset 2201-46135-001 SIP or Skype
$17.98