My favorite mega-tapped tavern is the Concordia Ale House. However you've got to get there, it's worth it. They have 22 taps, and they have a really interesting selection of regional and international beers that you're not likely to have had on tap before. They also have the best pub grub in the city. It's nonsmoking, the wait staff know their beer and are free with the tasters.
Concordia is great, absolutely great, for us beer dorks. And, they have a weekend breakfast that's very good.
They have 20some taps—and they have nothing commonplace on those taps. You know, the stuff that's on tap consistently around town - Widmer, Full Sail, Deschutes - you won't find it at Concordia. But there is this constantly turning over selection of really interesting things. They almost always have a double IPA, a cream ale, a weizen, a couple strong beers - really interesting stuff! There have been times when there hasn't been anything on the menu that I've tried before!
Another great thing is that they give you a draft list, which gives you the name, the style, the brewery, the country. The wait staff seem really into the beer, so they can give you a good description but it's nice not to have to guess from the name. They are also very free with the tasters.
In the cooler, they have over 100 bottled beers, also described in some detail in the bottled beer menu.
Their prices are really pretty reasonable for what you're getting, and you can choose a glass, pint, imperial pint... I love that you can specifically order an imperial pint.
They also have pool tables! It's kinda noisy at times, but gosh, it's awfully good.