There are several people named Brendan Gregg. This one is me (2011):
This might be useful if you don't know what I look like and are trying to find me at some event (although I don't normally wear kurtas).
Conferences often ask for a head shot. Here's one from 2016:
Another older one from 2012:
For an amusing older photo, here I am fooling around with data center safety clothing, seated at a text console in (I think) 2001:
For another amusing picture, in 2006 I was accused of being a group of clones (due to the volume of software I was writing); so I created this: