It's probably the best 'particle simulator' I've ever played.
Site:
http://powdertoy.co.uk/I think it's the best, because of a lot of reasons.
FEATURESFirst, is that it has a function, with which you can save and load simulations, as they call them. -There is a community, that I am not sure the size of, which uploads many different simulations.

Note that that is only the first page, of many.
-Here is something that I'm making, but not finished with.

-If you would like to load that yourself, search "Light Looping," and you should find it.
As you saw in my creation, the most advanced part of this simulator, is its electricity simulations. -See those light things moving through the water and metal? Those are electrical currents.
They are being used to turn that 'light' in the middle off and on, off within a couple hundred milliseconds after being turned on.
-I can not further explain the electrical simulations, it is better to be learned hands-on. Metaphorically.
My personal favorite, many different elements and compounds which allow for explosions. -It has a section of particles, which is what they call the separate elements/compounds, dedicated to explosives and fire.
There is a section of this OP telling all of the particles in each section.
SECTIONS & PARTICLES (Walls not listed)Key Red = Melting/Combustion point. Blue = Extra information. Green = Interaction with other particles.Electronics Ray Emmitter [ARAY]
Wifi Transmitter [WIFI]
Pump [PUMP]
Heat Switch [HSWC]
Electrically-Activated Cloner [PCLN]
Insulated Wire [INWR]
Switch [SWCH]
Liquid Crystal [LCRY]
Battery [BTRY]
Electrode [ETRD]
Lightning [THDR]
Use this is you want to get rid of something with great speed. Semi-Conductor (Cold) [PTCT]
Semi-Conductor (Hot) [NTCT]
N-Type Silicon [NSCN]
P-Type Silicon [PSCN]
Photons [PHOT]
Spark [SPRK]
Puts a current on any conductor. Metal [METL]
1000°CExplosives Fireworks (First) [FWRK]
Fireworks (Second) [FIRW]
Thermite [THRM]
Liquid Rubidium [LRBD]
Rubidium [RBDM]
C-4 [C-4]
Nitro [NITR]
Gunpowder [GUN]
Fire [FIRE]
Gasses Oxygen [O2]
Smoke [SMKE]
Noble Gas [NBLE]
Plasma [PLSM]
Water Vapor [WTRV]
Gas [GAS]
Liquids Colloid [PSTE]
Bizarre [BIZR]
Glow [GLOW]
Liquid Oxygen [LO2]
Diesel [DESL]
Liquid Nitrogen [LN2]
Melted Wax [MWAX]
Saltwater [SLTW]
Distilled Water [DSTW]
Acid [ACID]
Lava [LAVA]
Oil [OIL]
Water [WATR]
Powders Gravity Opposer* [ANAR]
Velocity Dust [GRAV]
Broken Coal [BCOL]
Fuse Powder [FSEP]
Yeast [YEST]
Broken Glass [BGLA]
Sand [SAND]
Broken Metal [BRMT]
Salt [SALT]
Concrete [CNCT]
Snow [SNOW]
Stone [STNE]
Dust [DUST]
Solids Filter [FILT]
Shield [SHLD]
Invisible [INVS]
Vine [VINE]
Pipe [PIPE]
Sponge [SPNG]
2450°C Fuse [FUSE]
Brick [BRCK]
900°C Coal [COAL]
Nitrogen Ice [NICE]
Glass [GLAS]
1700°C Wax [WAX]
50°C Breakable Metal [BMTL]
Plant [PLNT]
Wood [WOOD]
Ice [ICE]
Goo [GOO]
Radioactive Portal Out [PRTO]
Portal In [PRTI]
Solid ISOZ [SIZS]
Radioactive Liquid [ISOZ]
Warp [WARP]
Deuterium Oxide [DEUT]
Anti-Matter [AMTR]
Uranium [URAN]
Plutonium [PLUT]
Neutrons [NEUT]
Special Breakable Clone [BCLN]
Sub-Zero Flame [CFLM]
Stickman [STKM]
White Hole [WHOL]
Black Hole [BHOL]
Insulator [INSL]
Diamond [DMND]
Void [VOID]
Clone [CLNE]
Erase [█
X█]
Vacuum [VAC]
Cool [COOL]
Heat [HEAT]
Air [AIR]
Life Stains [STAN]
Long Life [LLIF]
34 [34]
Diamoeba [DMOE]
Pseudo Life [PGOL]
Move Life Type
Amoeba [AMOE]
Day and Night [DANI]
2x2 [2X2]
Assimilation [ASIM]
High Life [HLIF]
Game of Life [GOL]
*Needs a better name.