Painting - Separate two rooms

I just moved into a new house and am in the process of painting and upgrading. The problem I am having is that the living room and dining room share a common wall (it almost looks like one large room). I want to separate the two rooms by painting the living room one color and the dining room another color. But, I just don't like the look of a straight line down the middle of a wall where the paint changes colors. There is a drywalled beam that comes down about two feet from the ceiling where the two "rooms" meet, but as mentioned the one wall is common for both rooms. I was thinking of putting a moulding down the wall, but I think it will look tacky. Though I am relatively good with the tools, I seem to lack decorative creativity. Help!!!

It may not be your cup of tea, but many people use a wallpaper border to handle this situation. You could choose one with both the colors of your two "new" rooms so it will compliment and separate both rooms.

This sounds like you could do a two feet wide shelving unit floor to molding. This is a great decorating separation you could put books and statues, vases that would pull the two colors in each room togeher.

I have seen this done like boxes stacked. If you put a back on the boxes you paint the back facing the living area the color of the dining area and the frame of the unit the color of the living area. This will result in a quarter of a wall on the dining side for a picture or something decorative.