Does anyone have experience or opinion with regard to running Bitcoin on a PC that's been encrypted with Truecrypt? The OS is Ubuntu 10.04 LTS.
What exactly do you mean ? Your question is quite unprecise.
I just installed Bitcoin on 10.04 on a Virtual Machine with /home encrypted and yeah, it works fine.
Also, i have been using a lot of apps with truecrypt hard drives on my More-Hardcore-Linux-Distribution(tm), and guess what:
they all work. Even data recovery utilities work on TC drives exactly the same way as on normal drives.