Either that or try target mode. But that might not be available at all since you might not have mutual ports between the machines that would support target. Might as well just copy them to the time capsule. Do you not have a spare USB HDD lying around to do it faster? How much data do you think you'd even have to save? And why don't you already have it? When I get a new machine I always migrate my files over. I haven't lost a file since 2001. (The last time I had a HDD crash without having a backup.)
Actually hoping I've already copied over one of them when I upgraded, but the other two are my parents' and they haven't upgraded to anything yet, they've just gone kinda wacky and don't use them anymore. Thanks for the reminder about target mode, forgot about that, hopefully these aren't too old that I can't use that.