The CW (CBS/Warner Bros.; see also CW Seed, Kids' WB, 4KidsTV, and Vortexx)
(launched in 2006 as a merger of UPN and The WB)
IMDb; official website; TV Tropes; Wikipedia

Note: I lost access to the CW in like July 2011, so there's a lot I've missed, both in series I had been watching, and series that debuted after I lost access. For awhile I managed to watch some things online, but after awhile I couldn't keep up, so I've fallen years behind on everything.

2000s
The Batman (9/23/2006 - 5/8/2008; s1-3 aired on The WB)
Legion of Super Heroes (9/23/2006 - 4/5/2008)
Gilmore Girls (9/26/2006 - 5/15/2007; s1-6 aired on The WB; miniseries streamed on Netflix in 2016)
Smallville (9/28/2006 - 5/13/2011; s1-5 aired on The WB)
Supernatural (9/28/2006 - present; s1 aired on The WB)
Everybody Hates Chris (10/1/2006 - 5/8/2009; s1 aired on UPN)
Veronica Mars (10/3/2006 - 5/22/2007; s1-2 aired on UPN; s4 streamed on Hulu in 2019)
Reaper (9/25/2007 - 5/26/2009)
Aliens in America (10/1/2007 - 5/18/2008)
The Spectacular Spider-Man (3/8/2008 - 6/14/2008; s2 aired on Disney XD)

2010s
Life Unexpected (1/18/2010 - 1/18/2011)
The Secret Circle (9/15/2011 - 5/10/2012)
Arrow (10/10/2012 - 1/28/2020)
The Tomorrow People (10/9/2013 - 5/5/2014)
Reign (10/17/2013 - 6/16/2017)
The 100 (3/19/2014 - present)
The Flash (10/7/2014 - present)
iZombie (3/17/2015 - 8/1/2019)
Supergirl (10/10/2016 - present; s1 aired on CBS)

stuff I want to see:
Batwoman
Black Lightning
Legends of Tomorrow
Nancy Drew
Riverdale
probably some other stuff