Robtex

Up: 209.216.48.0/22
Can't show all results, try to descend to a more specific CIDR
Down left: 209.216.50.0/24
Down right: 209.216.51.0/24
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
209.216.51.1	PTR	mailscanner7.dnssys.com
209.216.51.1	A	gw-209-216-51.anaserve.net
209.216.51.15	A	uaeresidents.com
209.216.51.25	PTR	ns.internet-canada.com
209.216.51.32	PTR	raq78.dnssys.com
209.216.51.33	A	mail.glazedandconfused.com
209.216.51.40	A	mail.computerinferno.com
209.216.51.40	A	mail.net-detective.com
209.216.51.47	PTR	ars-erotica.com
209.216.51.48	PTR	ns3.dnssys.com
209.216.51.52	PTR	raq100.dnssys.com
209.216.51.58	A	mail.julaineflick.com
209.216.51.58	A	mail.powerstonecommunications.com
209.216.51.58	A	mail.castlepeakmanagement.com
209.216.51.62	PTR	precisionweb.net
209.216.51.69	PTR	lax-vm-105.virtbiz.com
209.216.51.76	PTR	ns0.dnssys.com
209.216.51.80	PTR	22.com
209.216.51.92	PTR	209.216.51.92.static.sna.hosting.com
209.216.51.102	PTR	nextmillenium.com
209.216.51.104	PTR	e-sex.com
209.216.51.106	PTR	pornofile.com
209.216.51.108	PTR	sexplore.net
209.216.51.126	PTR	14.com
209.216.51.145	PTR	e-leasing.com
209.216.51.153	PTR	gaysex69.com
209.216.51.159	PTR	asphaltdesign.com
209.216.51.160	PTR	atomsmasher.net
209.216.51.161	PTR	olderladies.com
209.216.51.164	PTR	209.216.51.164.static.sna.hosting.com
209.216.51.170	PTR	purextc.com
209.216.51.181	PTR	sublimedirectory.com
209.216.51.182	PTR	softwaresidewalk.com
209.216.51.188	A	mail.ravinstyle.com
209.216.51.197	A	mail.sendemhere.com
209.216.51.197	A	sendemhere.com
209.216.51.237	PTR	209.216.51.237.static.sna.hosting.com
209.216.51.244	A	*.californiaenlinea.com
209.216.51.244	A	mail.nuevayorkenlinea.com
209.216.51.244	A	mail.californiaenlinea.com
209.216.51.254	A	gw2-209-216-51.anaserve.net