Robtex

Up: 91.203.98.0/23
Can't show all results, try to descend to a more specific CIDR
Down left: 91.203.99.0/25
Down right: 91.203.99.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
91.203.99.16	PTR	addons.opera.com
91.203.99.16	A	*.secretsign.operaunite.com
91.203.99.16	A	deepakphilip.operaunite.com
91.203.99.17	PTR	auth.opera.com
91.203.99.22	PTR	extension-updates.opera.com
91.203.99.22	A	gadget-updates.opera.com
91.203.99.23	A	operamini.jp
91.203.99.23	A	operasoftware.co.uk
91.203.99.23	A	operamini.ma
91.203.99.25	A+PTR	link.opera.com
91.203.99.29	PTR	xml.opera.com
91.203.99.36	PTR	sitecheck2.opera.com
91.203.99.52	A	xn--8ers71d.cn
91.203.99.52	A	chooseopera.com
91.203.99.52	A	operamini.tel
91.203.99.110	A+PTR	sql-oc.opera.com
91.203.99.196	A	p17-01.opera-mini.net
91.203.99.198	A	p16-08.opera-mini.net