In Lausanne, we have "le pub vous faites de-penser" stickers on many billboards. Translation: Advertising makes you de-think (a pun on "spend")
How about in a free magazine which advertises all such events? Or a website that does similar? Also listings of "What's On" in more general media.
In Lausanne specifically, those billboards are also works of art in their own right so I do enjoy them.
(minor nitpick: should be "la pub")