Me and my bf are both playing Spiral Knights through Steam on the same computer (until his gets fixed). Keep in mind that we do not use the same account and don't play at the same time. For some reason the game is sharing our daily regenerated energy. Which ever one of us plays earlier in the day gets to use up to 100 energy and the other gets whatever is left.
I guess I'm the only one having this problem since I couldn't find a thread about it.
Edit: I thought it might be caused by the fact that all Steam accounts on one computer use the same local content, so I tried to play with the online client and let him play through Steam but the login page says I can't create any more free accounts through this computer.
This is indented behavior. Free accounts used on the same computer share the same Mist Energy pool. Once you go back to using separate computers this will stop. More info on this can be found on the Energy FAQ on the wiki.