What about firmware rootkits in network card, hard drive, BIOS? Usually you can't just wipe it out.  If you've got bad luck you will get one of this in new computer.

You can't assume that Linux is secure system, although it is more secure than Windows (or less threatened). There is much work to do if you want to prepare Linux to work with high level of security (grsecurity, disk encryption, firewall, virtual machines for java, flash). Not to mention anonymity matter, it's time consuming even for pro users. That's why I mentioned ready solutions.

Hi, How many of You, would like to invest in computer with guarantee of safety (or just very, very safe)? There is no totally safe computers (with safe system) ready to buy on the market. Is there any reason why? or people don't care about theirs important data (bitcoin wallet!) safety? What do you think about idea: having computer only to work, invest, storing important data, etc.?