Robtex

Up: 66.245.96.0/20
Can't show all results, try to descend to a more specific CIDR
Down left: 66.245.96.0/22
Down right: 66.245.100.0/22

IP	Type	Hostname
66.245.99.36	A	user-11faop4.dsl.mindspring.com
66.245.99.96	A+PTR	user-11faor0.dsl.mindspring.com
66.245.100.186	A	user-11fap5q.dsl.mindspring.com
66.245.100.187	A	user-11fap5r.dsl.mindspring.com
66.245.102.212	A	user-11fapmk.dsl.mindspring.com
66.245.102.240	A+PTR	user-11fapng.dsl.mindspring.com
66.245.103.10	PTR	user-11fapoa.dsl.mindspring.com