[Catalyst] Browser Detection?

[John M. Dlugosz]

  I'm supposing that there must be something in the request object that lets me know if 
I'm serving to particular browsers, in particular to whatever version of IE.  Then, in 
some single place in the app, automatically digest that and stick a flag in the stash.  
Now, the TT files can test for that flag and skip advanced features or serve alternative 
content.

Has this already been swept up into a nice module of some kind?

If not, can you give me some pointers on those two things: how to tell what the browser 
is, and where to put the code so it's executed on every action?

Thanks.