I've been in fandom for a number of years now (since the end of 2003) and have spent most of that time being very mono-fannish.
My primary contributions to fandom has been vids and podfic, if you're interested in seeing those, you can visit my website at www.parakaproductions.com
If you'd like to remix any of my fandom offerings (that includes anything I created on this journal, such as meta), all the power to you. I don't have much fic but you're welcome to podfic it, write sequels or rewrite them entirely; whatever strikes your fancy.
Same goes with my vids, feel free to copy ideas or take clips if you need.
If I've podficed a story that you'd also like to podfic, don't let me hold you back (I don't actually think you need to ask first before repodding but if you were thinking about it, no need). And I'm sure there are other things that can be done with podfic, (sampling, remixing, etc). I will say though, that while I'm ok with my recording being used, I can't speak for the writer's whose words I'm performing, so you'll probably need to check with them as well.
If you want to do anything with my works or fannish presence, go for it, you don't need to ask first, so long as it's within fandom. I'm not necessarily opposed to my works being used outside, personally, but as a podficcer, the potential spotlight would shine on more than just me, it's something I think I'm going to avoid.
If you're comfortable doing so, I'd appreciate a link to whatever you make off my works. I think how fandom builds off itself and creates new works based off others is one of the coolest things ever.