It's done wonders for Ryan Gosling, Chuck Norris, and Rick Astley, and yes, a brand new meme revolving around John Cusack would be hugely effective in helping to make the actor just as beloved a part of pop culture as he once was.
As we've learned, some of the best publicity doesn't cost a cent. With the rise of viral videos and marketing, celebrities don't even need to make appearances or do press junkets to get into the public's good graces—merely surfacing on a site with a few choice corny words around a cut-out of their head does the trick just fine.
Just look at the out-of-the-blue comeback of Rick Astley shortly after the "Rickrolling" phenomenon took over the Internet; MTV Europe dubbed him the Best Act Ever. That's no small feat, especially from an artist whose video was released when the voters were probably babies.
In conclusion, never underestimate the power of the meme. Someone get Cusack's assistant on that, pronto!