How about Carmine Jewel or some other bush cherry?

Well, not plums, but serviceberries are very attractive dual purpose ornamental/edible shrubs, with white spring blooms and good fall color. They make great pies, jelly, etc.

Black and Red currants, gooseberries, bush cherries all should be happy in zone 5b.
olga

Thank you for your input. I was hoping to have more stone fruit options instead of berries. I have never had currants before but they are certainly something worth looking in to. Are bush cherry's good for fresh eating or just for jellys and jam?

I don't yet have personal experience with how dwarf sour cherries taste (I just planted 4 bushes this spring), but from what I understand, the Carmine Jewel is a bit sour, so it depends on your tastes. I planted two anyways, as I like things which are sour, yet have plenty of sugar (high brix content). The other type I planted was Crimson Passion, which should be a better choice for fresh eating. Neither would likely grow all the way to 8 feet- more like 6'.

For more info: http://www.fruit.usask.ca/dwarfsourcherries.html

I grew up eating currants, but many others find them a bit tart for fresh eating. They wouldn't get close to 8' tall either...Maybe 4-5'. But, if you are interested in currants, gooseberries would be another option.

If you go for serviceberries, be careful which one you get. They range from 6' to 30' tall. Regent and Fergie should stay around 6' tall.

Another option you may want to think about is a Kiwi trellis. They grow pretty quickly, so if you are looking for a screen it could be good. It does need pruning and a trellis though.

Kiwi is something that sounds interesting and I havent thought of them before. Can Kiwi grow in Kansas? I thought they were largely a tropical fruit. What kind of trellis are kiwi's grown on? Grape style or on like a fence panel or something? How do you prune kiwi?

Clearly I need to do some research on my own but any input would be great.

Search for Hardy Kiwi (not the fuzzy kind). They should be plenty hardy for your area. I just planted 5 this year. You can use a grape-style trellis, a T-trellis, or a pagoda.

Here is a link that might be useful: Hardy Kiwi