Stuff you wish you'd found out earlier.

[Wyld Karde]

The classic is, of course, when you find that pressing shift causes an infiltrator to hold their breath while sniping.

But I just found another forehead slapper.  Engineers can press 'b' while holding their MANA turret to deploy it as a second ammo pack.  You can cover two locations with resupply, or give up your first ammo pack for mines and still be able to get sweet resupply xp off that heavy who's busy trying to single-handedly hold off an enemy air squadron. 

[Andon]

What? This is awesome! I must remember this!

[Adept]

Thanks Wyld, I had no idea.

[Wyld Karde]

There's been a tweak to the whole MANA turret as ammo thing.  You can still turn it into an ammo pack using the 'b' key, but you can only have one ammo pack out at a time.
Still very useful if your main ammo pack slot has been changed to mines or whatever.