For those that were with this game at its height, you'll never forget. If you weren't, you'll never know.
I used to run with an Outfit called BMC, on Werner, the European server, and it was there that I first understood what an extraordinary, innovative and unique experience PS was.
I had been playing more or less solo for a few levels, and was assaulting an enemy held base with the bulk of our forces (or the zerg as I was later to know them). We were inside the base, but having trouble clearing a path to the control console. The enemy had a short respawn time and effective close combat weapons. As long as you can keep them from breaking out, you will eventually win the base as its energy reserves get drained, but that sort of attritional siege takes time and you risk losing momentum, not to mention assaults behind your own lines. I was just thinking that it was going to be a long battle when I spotted the silhouettes of two Galaxy dropships passing over the rear door of the base. Looking up I spotted at least 16 infantry supported by MAX units doing a perfect drop to the poorly defended area, without any messing around the lead player hacked open the door while his comrades covered him. I jumped down from the base wall and followed them in. They cut a swathe through the enemy, and it was obvious that they knew what they were doing, I followed them past corpses of the enemy, down two levels into the base, until they reached a locked door that I hadn't paid any attention to. Again, they set up a defence perimeter while their lead hacker made the breach. The MAX units entered the room and started laying into the lightning-swathed tower in the centre of the room. To my surprise, this was the base generator. Seconds later, the emergency base lights came on and I followed the MAX units out area - just in time - as it detonated behind us.
Once a base generator is down, the battle is all but over. Unless the defenders can repair it, they will no longer be able to respawn at the base. If you don't defend it, an organised team can strike at it and take it down. I had just witnessed that sort of textbook operation.
The leader of the group - a player called Ostekake - was obvious from his command armour, I commended him on his squad and he offered me a trial with the Outfit. I accepted, and once I had joined the Teamspeak channel this game opened up opportunities and vistas that I had not previously imagined possible from online gaming and have not experienced since from any of the other MMOs that I have played.
Much has been written about the game mechanics and balance of PS, but what I really remember is a superb and unique experience that has never been bettered for me in any online game.