My converstation with immigration on entry to the US went something like this
Wow! The US immigration service know that Linux is open source. (Or at least one employee at Mineappolis does)
First time I went to OSCon I was quite worried because it was the first time I was going back to the US after they'd almost kicked me out for working illegally. Yet it went:
# standard beginning
me: I'm giving a talk at a conference
him: about what?
me: computer stuff
him: what computer stuff?
me: XML and stuff
him: yeah, but what about XML?
me: (slightly surprised) err, it's about "XPath APIs" [this was a while back]
him: oh nice, could you write XSLT extensions with those?
* stunned silence*
me: err, sure...
him: Great! Have fun! Welcome to the US!
Quite frankly, it made me wonder what kind of training they go through. Also, I did worry about the IT economy in the US for a while