Typhoon is a set of free wargames rules for modern jet combat. From the author:
Typhoon is an introductory set of modern jet combat rules that does not require hex mats or any special flight stands for miniatures. It is designed as a quick playing, low complexity game for gamers who are interested in flying multiple aircraft with aircraft from the late 70s up to the Eurofighter and F-35.
Amazon offers a free Kindle Edition of Hardtack and Coffee.
Hardtack and Coffee or The Unwritten Story of Army Life (1887) is a memoir by John D. Billings. Billings was a veteran of the 10th Massachusetts Volunteer Light Artillery Battery in the American Civil War. Originally published in 1888, Hard Tack and Coffee quickly became a best seller, and is now considered one of the most important books written by a Civil War veteran. “Hard Tack and Coffee” is not about battles, but rather about how the common Union soldiers of the Civil War lived in camp and on the march. What would otherwise be a mundane subject is enlivened by Billings’ humorous prose.
Here’s a Java implementation of the old school game from SPI: Time Tripper.
The BBC has a great article on the continuing fascination with model trains.
Road to Hell is a set of free wargames rules for WWII skirmishes. The author writes:
1.0 SCALE
This is a skirmish game so one miniature represents one man and one model vehicle is one vehicle. One centimetre corresponds to around 2 metres and a turn represents 10-20 seconds of real time.
2.0 YOU WILL NEED…
You’ll need a couple of units or squads (one per player) of around 8-15 miniatures each to play Road to Hell (for more details see the Army lists), a few six-sided dice (hereafter referred to as d6) a ruler or tape-measure (all measurements are in cm) and a minimum recommended playing area that measure 80x80cm (30×30 inches) for 28mm figures and 60x60cm (2×2 feet) for 20mm figures. Considering that these are small skirmishes, scenery is very important. Avoid battles in open ground as they will be very lethal and not particularly satisfying