In 1999, in order to "stay competitive" the Red Sox announced plans to replace Fenway Park. The dimensions and wall heights were to be the same as the current Fenway but plans called for expansion of seating and additions of luxury areas and suties. From the looks of the design drawings/models that were released it seemed like "Fenway on Steroids". It really brings to mind exactly what their hated rivals, the Yankees, ended up doing in replacing Yankee Stadium.
Also like the new Yankee Stadium, the new Fenway Park was to be located just a short distance from its predecessor. In an attempt to quiet the project's detractors, the Sox plan was to keep portions of the old park like the monster and most of the infield area.
The plan never really gained traction in Boston due to financing issues and the Save Fenway Park movement. It died completely once the new Henry/Lucchino ownership decided to take on a massive renovation of the existing Fenway Park. Eleven years and over 500 sellouts (at the highest ticket prices in the league) later, its clear that the renovation was the right choice. Fenway Park is now nearing its 100th birthday (it was finished in 1912), hopefully it will see another hundred.
You can see these and more images of the New Fenway Park plan at StadiumPage.com.