Cleaned the chain & bike

It had been awhile since the last time I cleaned the chain & bike 

I used the Park Tools chain cleaning tool with simple green degreaser to first thoroughly clean the chain.
It took quite awhile (the chain was pretty dirty).
After, I applied a drop of lube to each chain roller (the roller & roller shaft are the only moving parts of the chain.
After applying lube, I cleaned off any excess lube on the outside links of the chain (lube on the outside links doesn't do any actual lubricating and only attracts dirt).
The one dark colored link on the bottom is the one that's removable. 

Also cleaned the rest of the bike (frame, wheels, drivetrain, etc.).
It would be ideal to clean & lube the chain monthly.
I'm probably closer to actually doing it once every 3 to 6 months...