I went to BevMo this weekend and bought most every German hefe-weizen, dark and otherwise, that they had in stock. It was foggy this morning, so I thought it might be chilly for lunch, so I thought we should try the dark beers -- turns out, it warmed up; didn't matter, we drank inside anyhow.
Here's a link to the Wikipedia article on Hefeweizen.
Here's what we had:

I liked this beer, it was dark and quite rich, more akin to a porter than our other tastings today. One fellow liked this one the best. I don't know if I'd go out of my way to buy it again, but it was pretty good.
http://beeradvocate.com/beer/profile/8346/41805
.jpg)
This was definitely today's champion. It was more similar to a traditional Hefeweizen -- "bock" indicates a strong, dark beer; it was strong, but it wasn't as dark as our other two samples. I'd like to stand this up against our reigning champion, the Ayinger Hefeweizen.
http://beeradvocate.com/beer/profile/1357/3673
.jpg)
This bad boy is super-malty; it's actually listed as a malt liquor, though its alcohol level was in the range of the other two. Just drinking at lunch, it was too malty for everyone -- but I could imagine it as a fun food pairing.
http://beeradvocate.com/beer/profile/252/779