I checked the md5sum for the .deb I downloaded from http://www.opera.com/download/guide/?os=linux-i386, and I got 272929c189608dd22a9f61fb0000a365.  This number is not listed on http://ftp.opera.com/pub/opera-developer/info/md5sum.txt, and the only place it shows up is on a website that claims to be run by the Swedish university computer network, and a few other random sites. Is this .deb file trustworthy?  Why should I trust it if the only matching hash comes from a website that isn't Opera's?
Incorrect Md5sum for Opera
software installation;opera
I see the MD5 sum you mention there:http://ftp.opera.com/pub/opera/info/md5sum.txt272929c189608dd22a9f61fb0000a365  pub/opera/linux/1216/opera_12.16.1860_i386.deb