Robtex

Up: 66.90.184.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 66.90.188.0/23
Down right: 66.90.190.0/23
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
66.90.188.53	A+PTR	66-90-188-53.dyn.grandenetworks.net
66.90.188.70	A+PTR	66-90-188-70.dyn.grandenetworks.net
66.90.188.183	PTR	66-90-188-183.dyn.grandenetworks.net
66.90.188.196	A+PTR	66-90-188-196.dyn.grandenetworks.net
66.90.188.233	A+PTR	66-90-188-233.dyn.grandenetworks.net
66.90.188.235	A+PTR	66-90-188-235.dyn.grandenetworks.net
66.90.188.250	A+PTR	66-90-188-250.dyn.grandenetworks.net
66.90.189.195	A	66-90-189-195.dyn.grandenetworks.net
66.90.190.2	A+PTR	66-90-190-2.static.grandenetworks.net
66.90.190.2	A	afw.traq.com
66.90.190.12	A	mail.traq.com
66.90.190.43	A+PTR	mx.pfisd.net
66.90.190.43	A	mx.pflugervilleisd.net
66.90.190.43	A	spam.pfisd.net
66.90.190.57	A+PTR	www.pfisd.net
66.90.190.57	A	pflugervilleisd.net
66.90.190.57	A	www.pflugervilleisd.net
66.90.190.61	A	66-90-190-61.static.grandenetworks.net
66.90.190.142	PTR	66-90-190-142.static.grandenetworks.net
66.90.190.189	A+PTR	66-90-190-189.static.grandenetworks.net
66.90.190.210	A+PTR	66-90-190-210.static.grandenetworks.net
66.90.190.250	A+PTR	66-90-190-250.static.grandenetworks.net
66.90.190.251	A+PTR	66-90-190-251.static.grandenetworks.net
66.90.191.1	A+PTR	66-90-191-1.dyn.grandenetworks.net
66.90.191.3	A+PTR	66-90-191-3.dyn.grandenetworks.net
66.90.191.34	A+PTR	66-90-191-34.dyn.grandenetworks.net
66.90.191.73	A	66-90-191-73.dyn.grandenetworks.net
66.90.191.148	A+PTR	66-90-191-148.dyn.grandenetworks.net
66.90.191.161	A+PTR	66-90-191-161.dyn.grandenetworks.net