The threat of panda damage has kept me away from a bamboo frame. :D

Got one for you if you want change your mind...
 

And fire.

(warning, pointless digression ahead)

My wedding ring is tungsten. I thought it looked cool and would be more durable for my semi-active lifestyle. It still looks cool, but on a somewhat ironic note I no longer wear it on bike rides because it fell off my finger once during a ride and it was only through blind luck that I found it again.

Tungsten is very strong - I can't quantify it but I'm sure you can easily research its properties. I think it might be stronger than Ti. Naturally I wondered why there are no bikes made from Tungsten. After some minor internet research the short answer is basically that it's way too stiff and brittle, not good for large objects such as bicycles. I think I saw a prototype mountain bike made out of Tungsten but I think it was a concept only.
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After seeing some Chevy vs. Ford "Aluminum trucks are bad/no aluminum trucks are good" commercials I was amused because the aluminum vs. steel debate happened 30 years ago in bikes, and now we've all moved on to carbon fiber vs. titanium. It made me wonder why we haven't seen titanium cars? I looked into that as well, there's a couple super-expensive titanium supercars out there but as I recall the expense makes it not an ideal choice for big things like cars. (Although it was a good choice for the SR-71 Blackbird, which I guess illustrates the advantages of having the might and wealth of the western military-industrial complex behind you).

I'm sorry, what's this thread about? Oh yeah. Titanium is basically the same as aluminum foil. Got it.

Tungsten is also very heavy. like 19,7kg/l or so.

Absolutely ti is the only forever frame material. Take all 4 frames and bury them in the back yard. Now go dig them up 10 years later. Ti will still look and ride new.
Of course only us ti riders know how important this is.