Like the title says.. here are some examples of 2 projects I know of

Milkyway@home: Can generate WUs designed for however many cores you sent boinc to allow, and they run very fast and can rack up credit. Unfortunately they don't let you configure their project very well, and you get single core CPU WUs mixed in.

MooWrapper: Can generate multi GPU WUs to use more than 1 GPU at a time for the WU

If anyone knows of any other "multi" resource projects like that, please let me know.