Live monitoring of various parts and pieces of the USA and CA grid.
Please note that these sites are not really intended for general
consumption and are more of a monitoring site for power speculators
and investors.


Federal Energy Regulatory Commission.  See "Electric Power Markets".
https://www.ferc.gov/market-oversight/mkt-electric/overview.asp

California Independent Service Operators:
http://www.caiso.com
http://www.caiso.com/Pages/TodaysOutlook.aspx
There's quite a bit on the CAISO site, but much of it is buried under
a terminally disorganized web pile and various security obstructions.
In the past, there was considerably more information available to the
public.  However every time there's a security incident, the available
information is reduced.

Independent Service Operators of New England:
https://www.iso-ne.com
https://www.iso-ne.com/isoexpress/

Midcontinent Independent System Operators
https://www.misoenergy.org

New York ISO
http://www.nyiso.com/public/index.jsp
http://www.nyiso.com/public/markets_operations/market_data/maps/index.jsp?load=DAM

Electric Reliability Council of Texas
http://www.ercot.com

New Brunswick Power System Operator
https://tso.nbpower.com/Public/en/op/

Independent Electricity System Operator (Ontario Canada)
http://www.ieso.ca
http://www.ieso.ca/power-data

Southwest Power Pool
https://www.spp.org
http://pricecontourmap.spp.org/pricecontourmap/

There are others but I'm too lazy to find them.