Robtex

Up: 72.249.40.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 72.249.40.0/23
Down right: 72.249.42.0/23
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
72.249.40.5	PTR	smtp1.alphainternet.com
72.249.40.17	A	mycubicleguy.com
72.249.40.56	A	ecnsupplies.com
72.249.40.100	PTR	mail.alphainternet.com
72.249.40.200	PTR	mail.alphainternet.com
72.249.40.202	PTR	level2.alphainternet.com
72.249.40.205	PTR	mail.dougstanleyford.com
72.249.40.226	A	server3.cbmailserver.com
72.249.40.227	A	mail.alphaip.com
72.249.40.241	PTR	mail.luxuryhomeproducts.com
72.249.40.241	A	mail.decorativefinishes.net
72.249.41.1	A	gw.lavabit.com
72.249.41.2	A+PTR	ashlee.lavabit.com
72.249.41.2	A	switch.lavabit.com
72.249.41.10	A+PTR	ns1.lavabit.com
72.249.41.11	A+PTR	ns2.lavabit.com
72.249.41.12	A+PTR	ns3.lavabit.com
72.249.41.13	A+PTR	ns4.lavabit.com
72.249.41.28	A	28-72.249.41.lavabit.com
72.249.41.32	A	kelly.lavabit.com
72.249.41.33	A+PTR	karen.lavabit.com
72.249.41.34	A	lauren.lavabit.com
72.249.41.35	PTR	lacey.lavabit.com
72.249.41.35	A	jfte.com
72.249.41.41	PTR	41-72.249.41.lavabit.com
72.249.41.41	A	ns2.magma-daemon.com
72.249.41.41	A	ns1.magma-daemon.com
72.249.41.50	A+PTR	mail.nerdshack.com
72.249.41.51	A+PTR	www.nerdshack.com
72.249.41.51	A	www.mailshack.com
72.249.41.52	PTR	lavabit.com
72.249.41.52	A	pop.lavabit.com
72.249.41.52	A	www.lavabit.com
72.249.41.54	A	liberty.lavabit.com
72.249.41.61	PTR	61-72.249.41.lavabit.com
72.249.41.61	A	ns1.magmadaemon.org
72.249.41.61	A	ns2.magmadaemon.org
72.249.41.91	A	91-72.249.41.lavabit.com
72.249.41.126	A	stacie.lavabit.com
72.249.41.129	A	129-72.249.41.lavabit.com
72.249.41.130	A	hosting.lavabit.com
72.249.41.130	A	cp.razorsites.com
72.249.41.135	A	135-72.249.41.lavabit.com
72.249.41.140	A+PTR	ns1.hosting.lavabit.com
72.249.41.142	PTR	ns2.hosting.lavabit.com
72.249.41.142	A	ns2.razorsites.com
72.249.41.144	A	mail.dfwcorporatepark.com
72.249.41.144	A	mail.razorsites.com
72.249.41.145	A	249.41.hosting.lavabit.com
72.249.41.147	A	mssql1.razorsites.com
72.249.41.148	A	antiquehorology.com
72.249.41.148	A	ns4.razorsites.com
72.249.41.148	A	dfwcorporatepark.com
72.249.41.162	A+PTR	162-72.249.41.lavabit.com
72.249.41.200	A+PTR	200-72.249.41.lavabit.com
72.249.41.209	A	209-72.249.41.lavabit.com
72.249.41.221	PTR	admas.phantom.lavabit.com
72.249.41.221	A	ns1.magmadaemon.com
72.249.41.221	A	ns2.magmadaemon.com
72.249.41.230	A	12inchpimps.com
72.249.41.230	A	willietrimmer.com
72.249.41.230	A	azimuthartz.com
72.249.41.235	PTR	osheana.virtual.lavabit.com
72.249.41.235	A	darkmail.info
72.249.41.235	A	mx.darkmail.info
72.249.41.239	A+PTR	239-72.249.41.lavabit.com
72.249.41.239	A	www.whodoyouknowat.com
72.249.41.239	A	whodoyouknowat.com
72.249.41.246	A+PTR	246-72.249.41.lavabit.com
72.249.41.255	A+PTR	255-72.249.41.lavabit.com