If you mean sharing program then 512 MB RAM (It is MB:wink may not be enough to run two or more at once and may inhibit other uses of your computer that you may want.

You could test it though, but there are steps that need to be taken if you do this.

Like setting the Max upload speed in both Limewire and the other program. e.g. You have max 50 KB/s then set 20 KB/s for Limewire, 20 KB/s for the other programs and leave ten for messages between the programs and other internet usage. Do the same with the download speed. Also don't allow Limewire to go into UltraPeer mode no matter what your speed is (because of higher RAM usage). Same thing with allowing few downloads and Uploads simultaneously in both programs

Also if using a router set up portforwarding for both programs. Different port for each program.

More advice here www.portforward.com

Also set up advanced rules in your firewall for opening the ports that you use (both TCP and UDP , Incoming and Outgoing.

You'll need to get a bit computer savvy to do things like running multiple sharing programs at the same time and I would suggest that you get more RAM (At least 1024 MB)

Also this depends very much on the speed of your internet connection, how good your router is at handling multiple connections and other things.