That's right, 4 PetaFLOPS, that's 4 Quadrillion Floating Point Operations per Second. We have reached a new echelon of performance. See for yourself in the "Server Status" link on the top right of the on the website.

I remember last year's max was a 'mere' 2.5 PetaFLOPS.

Pretty amazing :)

On 2019/01/05 at 09:44 UTC the reading was 4,004,287 GigaFLOPs (4.004287 PetaFLOPs). I took a screenshot ;-)

Back at the turn of the century I recall wanting to model the conformation of some peptides (~20-30 amino acids). I found this website from Prof Baker called Rosetta. He allowed folks to upload their aa sequence and it joined the queue to get folded. A few weeks later I'd get one back, spin it around and decide I needed to change the shape of the epitope so I'd change a couple of amino acids and submit it again. A few weeks later, repeat...

Stopping by Woods on a Snowy Evening by Robert Frost

Whose woods these are I think I know.   
His house is in the village though;   
He will not see me stopping here   
To watch his woods fill up with snow.   

My little horse must think it queer   
To stop without a farmhouse near   
Between the woods and frozen lake   
The darkest evening of the year.   

He gives his harness bells a shake   
To ask if there is some mistake.   
The only other sound’s the sweep   
Of easy wind and downy flake.   

The woods are lovely, dark and deep,   
But I have promises to keep,   
And miles to go before I sleep,   
And miles to go before I sleep.

And miles to go yet...

This is great news!
This project passed over the 1 PetaFLOPS in 3 Feb 2013.
You should know that this is a theoretical value reverse calculated from the credits awarded per day (dividing it by 200 - this number comes from the definition of the BOINC credits). As the credits awarded here consist of 50% bonus for returning the result within 24 hours (or 25% for within 48 hours), the actual PetaFLOPS is lower (it's around 2.5 PetaFLOPS). No to mention that the "basic" credits also come from an estimation.

As shown in GPUGrid Server Status page:
http://www.gpugrid.net/server_status.php
Possibly due to the lack of tasks for Linux systems, current computation power has dropped below 2 PetaFLOPs.
This is about half the value reached at the beginning of this year.
January 2019 was a great month!
Based on my screenshot from that time, there were ACEMD short and long tasks in progress for both Windows and Linux systems, and also Quantum Chemistry tasks for Linux ones...
I'm sure that better times are still to come.