Sure, start a new comp, use the import dialogue, but instead of selecting assets, select the other projects. You may end up with multiple assets, so you can try(it doesn't always get everything)---File > Consolidate all footage.
Johnny Cuevas, Editor
"I have not failed 700 times. I have succeeded in proving that those 700 ways will not work. When I have eliminated the ways that will not work, I will find the way that will work."
---THOMAS EDISON on inventing the light bulb.