We had been assigned to recover a RTI from a corporation in Boston called SilverTech. We got into the building with no problems, and even got around the security guard at the loading dock, because we had mages scouting in [astral space]. However, we had no clue where the aforementioned [RTI] actually was within the building. 
By the time we found it, (installed inconveniently inside the head of an NPC), the rather-disorganized party had managed to set off an alarm or three. 

[BFG]s started coming literally out of the walls (and ceiling) but we managed to get out of the building and into the van. Our rigger started driving as fast as the old van would go away from the [RenRaku Security] [HoverTank]s, which, obviously, wasn't fast enough. This was when one of our mages started trying to be clever...

She summoned a CitySpirit, and told it "Make us go faster!" So, it did. From our car's perspective, we were going about 90 (an insane speed in that old a van) but from the rigger's driving perspective, we were actually going about 300 MPH. This was not-so-good, but we managed to hold it together. (Or, she did).
Unfortunately, the [HoverTank]s were still gaining on us, and they were firing anti-tank rounds at us, so our mage summoned another city spirit, and said "MAKE US GO FASTER!"

At this point, we were going about 900 MPH from our rigger's perspective, when one of those anti-tank rounds took out our engine. Oops. There was a fantastic explosion, and a phenomenal crash.

Four of the twelve party members survived (and three were captured)-- 

 * One was the driver. She had a seatbelt on.

 * Two (myself included) were just lucky. Really lucky.

 * One was invisible, not-yet known to the party, and therefore not in the car at all. He managed to salvage the head of the NPC with the RTI in it, and the box of other [RTI]s that we had run off with "just because".

Our Epitaph: Do not summon what you can not slow down

Or: Always wear your seatbelt