craftgrrl | Question about posterity....

I'm new to this community (I didn't know LJ had one!). I've been inspired by a lot of what I've read from the past few days. I've always been sort of crafty when it comes to collages and stuff, though I've dabbled in my share of crafts (some successful and some *not* so successful...).

But, I have a question that someone might be able to give me the answer to. I've been toying around with an idea for months. My husband has been dying for a coffee table and I am dying to finally put something in our apartment that screams my personality and not his. :) Instead of buying your typical "Target/LNT/BB&B" coffee table, I wanted to do a collaged top of clippings I've accumlated over the years from various fashion/entertainment magazines and work with a piece of unfinished furniture. My problem is that I want it to last the test of time somewhat. What would I need to do to waterproof it and still keep the magazine pictures intact? I'm guessing that for a task like this, simple decoupage is just not enough (though I saw only that done on a craft show to a wooden chest). Would I have to use some kind of better sealant? I'm at a loss... Any and all help would be most appreciated!