SM 1U SuperServer 5015MT+ Core2/Xeon
Intel Core 2 Duo E6420 2.13GHZ FSB1066 4MB
2 x Kingston 2GB DDR2 667 PC5300
Seagate 160gb 7200rpm SATA II
Digium TE110P ISDN-30 interface OR Digium TE120P 1 poorts ISDN-30

Running Asterisk on Debian, dedicated (asterisk will be compiled, not the debian packages)
Max. number of open channels will be 15 (though 99% of the time it won't exceed 10).