Robtex

Up: 64.21.248.0/23
Can't show all results, try to descend to a more specific CIDR
Down left: 64.21.248.0/25
Down right: 64.21.248.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
64.21.248.0	A+PTR	ip-64-21-248-0.far.ideaone.net
64.21.248.99	PTR	ip-64-21-248-99.far.ideaone.net
64.21.248.187	A+PTR	ip-64-21-248-187.far.ideaone.net
64.21.248.187	A	loghomeinsurance.net
64.21.248.187	A	fulcrum.biz
64.21.248.190	A+PTR	mail.tepinc.com
64.21.248.196	A	mail.parkcompany.com
64.21.248.200	A	stahc.net
64.21.248.204	A	mail.studenttransitions.com
64.21.248.222	A	labtech.imstcs.com
64.21.248.234	A	mail.valleywirelessnd.com
64.21.248.244	A	mail.npc-net.com