SSH TUNNEL for other laptops through a mac mini?

Hello everyone, if this is indeed possible I think it will be an easy one for all of you.

OK, currently I do the following to set up a proxy server to use while browsing.

ssh -D 9999 user@blah.blah.com

then I set up Firefox to use localhost and port 9999 as the SOCKS proxy. I am doing that now and everything is OK.

Currently that blah.blah.com is a hosted machine that I pay for. I am tunneling through it on my laptop.

Sometimes I also have my wife do the same, so I have to go over to her laptop and do the ssh -D deal and put in my password for that hosted machine.

Now, we also have a mac mini in the house that we both have access to.

Could I do the ssh -D 9999 user@blah.blah.com on the Mac Mini, leave it up and running all the time, and instead of setting Firefox to use "localhost" and port 9999, set Firefox on both of our machines to use MAC.MINI.IP.ADDY and port 9999 so that that tunnel is always available?

I tried this out and it wasn't working... but I guess I'm just doing something wrong.

Let me know if this makes sense, and if there is anyway I can do it!

Thanks for any help.

- harvey