Robtex

Up: 216.244.24.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 216.244.28.0/23
Down right: 216.244.30.0/23

IP	Type	Hostname
216.244.28.10	A+PTR	user-3cf870a.dsl.mindspring.com
216.244.28.20	A+PTR	user-3cf870k.dsl.mindspring.com
216.244.28.68	PTR	user-3cf8724.dsl.mindspring.com
216.244.28.79	A+PTR	user-3cf872f.dsl.mindspring.com
216.244.28.189	A+PTR	user-3cf875t.dsl.mindspring.com
216.244.28.205	A+PTR	user-3cf876d.dsl.mindspring.com
216.244.29.44	A+PTR	user-3cf879c.dsl.mindspring.com
216.244.29.108	A+PTR	user-3cf87bc.dsl.mindspring.com
216.244.29.177	A+PTR	user-3cf87dh.dsl.mindspring.com
216.244.29.188	A+PTR	user-3cf87ds.dsl.mindspring.com
216.244.29.201	A+PTR	user-3cf87e9.dsl.mindspring.com
216.244.30.36	A	user-3cf87h4.dsl.mindspring.com
216.244.30.104	PTR	user-3cf87j8.dsl.mindspring.com
216.244.30.152	A+PTR	user-3cf87ko.dsl.mindspring.com
216.244.30.183	A+PTR	user-3cf87ln.dsl.mindspring.com
216.244.30.199	A+PTR	user-3cf87m7.dsl.mindspring.com
216.244.30.240	A+PTR	user-3cf87ng.dsl.mindspring.com
216.244.31.100	A+PTR	user-3cf87r4.dsl.mindspring.com
216.244.31.155	A+PTR	user-3cf87sr.dsl.mindspring.com
216.244.31.242	A+PTR	user-3cf87vi.dsl.mindspring.com