Download portable Opera 23.0.1522.75 & 12.17.1863 32-64 bit Multilingual

Fast and free Web browser without installation.
Download Portable Opera Developer Online (0.5 MB)
In first screen enter:25.0.1583.1
Download Portable Opera Next Online (0.5 MB)
In first screen enter: 24.0.1558.25
Download Portable Opera Online (0.5 MB)
In first screen enter: 23.0.1522.75
Download Portable Opera 12 32-64 bit Online (0.5 MB)
In first screen enter: 1217
Download Portable Opera Mail Online (0.5 MB)
In first screen enter: 1.0-1040

OperaPassView Recover the passwords stored in Opera 12 Web browser.
Download Portable OperaPassView latest Online (0.5 MB)

Flash Plugin

Can use Java Runtime Environment Portable

Extract and run OperaDeveloperPortable or OperaNextPortable or OperaChromePortable or OperaPortable (each have their own profile) or OperaMailPortable.