I use several methods.. and I don't go out looking for viruses mind you, I only get ones that I've managed to capture in the wild. When I started doing this it was in 1995 and I worked for my college tech staff... when a lab computer or more often a professor (the things I found on their hard drives looolz) managed to get infected, I would simply be running virus scans using manual options.. that is, when an infection is found, prompt for action instead of automtically using repair, quarantine or delete.. when I was prompted I'd slide a floppy in and copy the infected file.
I've since found quarantine itself to be a pretty viable option.. ack gtg.. at work and my boss called a meeting.. i'll elaborate more when i can..
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Back from my meeting, So I'll add a bit more. As for what I do with viruses now, is I save them on a USB stick instead of a floppy. From executables to dll's, to various infected media types like .mov and the wimad infected .m4a, pdf vulnerabilities, infected screensavers, .pif's and browser plugins (more malware than virus).. a vast majority of what I have is pretty dormant on it's own, requiring a trigger like a windows startup command or a registry entry.. In the case of where I know explicitly what triggered the virus in the first place I will often get a download of that... things like The Gator Toolbar, Search Assistant and WinProtector 2010. I try to sort them either based on what they do or how they work, like all the infected .dll's i put in a folder called /drivers - and I have worked out some control programs that attempt to install as much as possible either if the computer is booted from USB boot or from autorun if a play or run option is used. I have a junk pc that I tend to re-install OS on once a week that is sort of a playground... there is no point to it really just, I guess like someone who works in pest control to have a collection of bugs at home...
it's more like a catalog of the enemies i've faced! Sometimes there is a story behind them... like an e-mail attachment that my boss opened even after I sent a company wide e-mail and white paper saying.. don't open attachments titled "I Love You". I guess that's it.. and until you asked I've never really thought about it all that much.. just a little hobby I guess and never thought it all that odd.