Merging PDFs by Command-line

No seriously, this is so much better than rebooting into Windows or starting up wine to open Acrobat, which I have to pay for, and then combing documents into a ‘binder.pdf’.  Then I have to rename it and so forth.

Meanwhile by command-line in Ubuntu I could have just gone:

pdfunite in-1.pdf in-2.pdf in-n.pdf out.pdf

Thank you Stack Overflow.