All posts to the site are made subject the the Creative Commons 'Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0)' license. The summary of this license says:
You are free:
- to Share — to copy, distribute and transmit the work
- to Remix — to adapt the work
- to make commercial use of the work
which is a key point of the site: you can take material here and reuse it elsewhere without further permissions. The license also says
Attribution — You must attribute the work in the manner specified by
the author or licensor (but not in any way that suggests that they
endorse you or your use of the work).
Share Alike — If you alter, transform, or build upon this work, you
may distribute the resulting work only under the same or similar
license to this one.
along with various other things.
My reading of this is that you can take code posted here and package it up for distribution, provided you pick a suitably 'free' license and make attribution. The most obvious way to do that would be to simply use the CC license directly. The part that says 'or similar' suggests to me that something like the LPPL with an attribution statement would also be suitable, although these things are complex. [The full legal license seems to go into some detail about 'similar', and it I guess it would be safest to stick to the CC license!]
[Of course, in cases where you can contact the original author then some of the conditions may be relaxed.]