add intro

NetRNGs.md

@@ -183,6 +183,11 @@ fishermen, which sounds problematic.
 # Timing
 
 TODO: Comment on relative block time vs. more absolute synced clock times.
+  ability to have timeout that depend on network activity?  (relative absolute time??)
+  but think about the network conditions
+
+We seemingly need a bound on clock skew between validators, which
+we must enforce using the peer-to-peer network.
 
 ### RANDAO
 
@@ -199,3 +204,10 @@ slower than the overall network, but as their stake increases this
 rate goes up.  Ouroboros wants to prevent this initial slow start,
 but this requires 
 
+
+
+### Ideas
+
+Unavailability game
+Time or relative time signing
+