Yawgmoth, Thran Physician allows you to pay life and sacrifice creatures to spread -1/-1 counters around and draw cards
This artifact can be used to fill everyones hand, but it can also be used to mill everyone
Blazing Archon - Expensive, but once it hits the field, none of your opponents' creatures can attack you until someone finds removal
Its a fun tech card for commanders like Blim, Comedic Genius or Zedruu the Greathearted, where you can grab your Mountain and pin the Guides negative effect on another player
Just like the Construct suggests, I really like this with artifact tokens like the recent Soldiers, Thopters, Myr, Servos, and more
You can check out the mechanics article to get a full sense of what's going on