There were some folks at the prophetic summit this week that have a ministry called The Sign, and 818 is the number of the SIG. Very cool.
Will Ford leads it, and he has the most amazing story.
He gave this verse for 818.
Isaiah 8:18 NASBS
[18] Behold, I and the children whom the LORD has given me are for signs and wonders in Israel from the LORD of hosts, who dwells on Mount Zion.
This rings true to me. God has often made me a sign.