Uplink: Hacker Elite

There is an IRC Client which can be downloaded via the Uplink Internal System however there is no multi user play available.

No. The game itself might be quite confusing about this part. As there is a multi screen option and an IRC client one might assume you can hack simultaneously with someone else and see who's faster, or to compare some other criteria. However, this has not been made possible. Modlink.net once had a contest going to test ultimate speed with certain requirement to meet asap and post your times afterwards, this was nonetheless canceled soon thereafter, for a reason I do not know.