MacOS – Installing Flash for Firefox on OSX without admin rights

How-To-Geek had an article about installing Flash 9 in FireFox manually. Follow the steps to install into your profile not the All Users profile, as that will probably be locked down by the Corporate IT Department. I haven't tested it with Flash 10 myself.

I would warn however that your IT department may well frown upon installing Flash 10 this way. Depending on the organisations policies, manually installing software could be breaking the companies Acceptable Use Policy.

This may be what you want: Create a Sandbox for apps using folder actions