If you're going to Barcelona next month for VMworld 2015, one thing I can thoroughly recommend are the vBrownBag TechTalks that take place in the Hang Space.
If you're not familiar with them, these TechTalks are 10 minutes long and given by anybody from the virtualisation community with something interesting to share. So, if you have a gap between sessions or there's something of interest on the TechTalk schedule (this is published closer to the time) then they're well worth listening to.
Of course, it may be that you have something you could talk about for 10 minutes. If so, why not propose a session using this Google Form?