a low resource MEGA pack of many addons merged with realism patches
http://www.flightsimhq.org/ysflight/
Original features:
One mega pack download
includes many addons
Linux 32bit 64bit
openGL 1 & 2
runs on Linux wine also
Windows (untested)
specializing in guns combat
gunpower & gun rate
custom eras, or by year
aircraft:flight envelopes
improved hit bubbles
no installer, no spyware, no adware
over 1000 ground objects for map & mission builders