Robtex

Up: 66.245.64.0/19
Can't show all results, try to descend to a more specific CIDR
Down left: 66.245.80.0/21
Down right: 66.245.88.0/21

IP	Type	Hostname
66.245.80.97	A	user-11fak31.dsl.mindspring.com
66.245.81.204	A	user-11fakec.dsl.mindspring.com
66.245.83.241	A	user-11fakvh.dsl.mindspring.com
66.245.84.13	A	dgaforms.dekalbgastro.com
66.245.84.255	A	user-11fal7v.dsl.mindspring.com
66.245.85.28	A	user-11fal8s.dsl.mindspring.com
66.245.86.129	PTR	user-11falk1.dsl.mindspring.com
66.245.86.151	A	user-11falkn.dsl.mindspring.com
66.245.88.21	A	user-11fam0l.dsl.mindspring.com
66.245.88.69	A	user-11fam25.dsl.mindspring.com
66.245.88.89	A	user-11fam2p.dsl.mindspring.com
66.245.89.205	A	user-11famed.dsl.mindspring.com
66.245.91.172	A	user-11famtc.dsl.mindspring.com
66.245.91.209	PTR	user-11famuh.dsl.mindspring.com
66.245.93.152	A	user-11fanco.dsl.mindspring.com
66.245.95.144	PTR	user-11fansg.dsl.mindspring.com