according to trickle's man page, http://linux.die.net/man/1/trickle i can limit the download speed of a process, e.g.

trickle -u 10 -d 20 ncftp to Launch ncftp(1) limiting its upload capacity to 10 KB/s, and download capacity at 20 KB/s.

how would I go about limiting google-chrome or firefox with trickle?

Edit: For those of you asking why I asked such an obvious question, I tried

trickle -u 10 -d 20 firefox

and I'm getting an error

trickle: Could not reach trickled, working independently: No such file or directory

firefox opens right after, but is definitely not rate limited...