What gzip_types are recommended?

[KT Walrus]

What gzip_types are safe to compress with most  browsers?  Can  
javascript and css be safely compressed?

http://wiki.codemongers.com/NginxHttpGzipModule#gzip_types

Might be nice to update the link above with the answer.

Also, can I make sure that Javascript and CSS files are cached for the  
user and can I set an Expires: time for these file types?

Thanks.  I'm new to nginx and I am trying it out to see how much it  
helps with performance for a PHP coded forum site.

Kevin