OnionDSL – A DSL Connection Directly into the Tor Network
kickstarter.com
kickstarter.com
Tor Browser has been heavily modified in order to try to prevent cross-session tracking (and some other privacy and security threats):
https://www.torproject.org/projects/torbrowser/design/
If you used your regular Firefox or whatever with a Tor transparent proxy, as I think is proposed here, you would probably have cross-session and cross-site tracking using cookies and lots of other mechanisms, because the browser is just not that paranoid. This would reduce the privacy benefits of using Tor quite a bit.
So, the Tor Project has advocated against routers that automatically send everything over Tor, at least if end users are going to rely on that for privacy while using unmodified desktop software.
Edit: I sent the project creator a note about this on Kickstarter.
Edit 2: See also https://www.torproject.org/download/download.html.en#warning (advocating using Tor via Tor Browser and not any other browser because "[a]lmost any other web browser configuration is likely to be unsafe to use with Tor").