Robtex

Up: 216.44.0.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 216.44.0.0/23
Down right: 216.44.2.0/23

IP	Type	Hostname
216.44.1.1	A	mail.xthowis.com
216.44.1.1	A	cashman-gw.nerdsintheknow.com
216.44.1.3	A+PTR	mail.nerdsintheknow.com
216.44.1.12	A	perfprog.com
216.44.1.31	A	ken.nerdsintheknow.com
216.44.1.33	A	lists-lom.nerdsintheknow.com
216.44.1.34	A	myhero-bkup.nerdsintheknow.com
216.44.1.61	PTR	switch061.nerdsintheknow.com
216.44.1.68	PTR	masterswitch-ccanet-a.nerdsintheknow.com