Not sure if this is common knowledge.
http://steamstat.us/
Bookmark that if you use steam.
I was trying to buy Substance Designer Indie Bundle while it was on massive discount, about $150.
But the store was not working and time was running out on the sale.
So I kept an eye on that page and a few hours later it settled down and I made the purchase.
MISSION ACCOMPLISHED!
ACHIEVEMENT UNLOCKED!
Steam Service Status
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