I've used a coffee press to brew loose tea, with good results. I mostly use a tea press now (same principle, different shape!). The thing that's important to look out for is how well the plunger works. A good plunger will really press down hard on the leaves so the brewing process completely stops after the recommended brewing time. Otherwise you'll end up with bitter tea.

Thanks simpleleaf, I may pick one up!

Cool! Let me know how it works out.