typoscript browser switch

Sometimes you need to detect an user agent, something like a browser switch. In Typoscript you can do it very simple.

For Opera, providing a Opera specific css file.

[browser = opera]
page.includeCSS {
file5 = fileadmin/css/opera.css
}
[END]

For Internet Explorer and version equal or smaller than version 7

[browser = msie] && [version =< 7.0]
page.includeCSS {
file5 = fileadmin/css/ie7.css
}
[END]