--- a/hws/hw08.tex	Sun Nov 23 22:12:43 2014 +0000
+++ b/hws/hw08.tex	Sun Nov 23 22:32:00 2014 +0000
@@ -16,6 +16,10 @@
 \item (\textbf{Optional}) What is is the purpose of the
       proof-of-work puzzle in Bitcoins?      
 
+\item (\textbf{Optional}) The department has large labs full
+      of computers that are pretty much idle over night. Why
+      is it a bad idea to let them mine for Bitcoins?
+
 \end{enumerate}
 \end{document}