I've watched a very small list of animes, none of them the long-running type like this, so I have to ask: Why don't they just stop making shows until the manga is created? Are manga releases that unpredictable? Even then, and to be fair this is just me personally, but I'd rather see a tightly-wrapped story than a bunch of people standing around talking for multiple episodes. Unless their discussions are particularly endearing or interesting. In which case, talk away!
But yes, my question stands.
If you're curious about the shows I've watched: Cowboy Bebop, Lupin the 3rd, Evangelion, FLCL, Lain, Desert Punk, Trigun, Hellsing and Excel Saga. Maybe a couple others, but clearly not ones memorable enough to recount.