What to do with Pure Spam domains?

I have a few "pure spam" domains just sitting in my accounts. Most have great link profiles.

Should I be double 301'ing them? building them back up and getting them reviewed?

throwing them away?

Throwing away mate

If they don't get indexed, they are basically braindead. Not to mention 301 redirects pass penalties as well.

And trying to get them reviewed is more trouble than it's worth really.