Nothing you can do easily and not with vanilla AE, anyway. The example you posted is a fluid simulation from a 3D program (though a very poorly tweaked one) and that's pretty much the answer here: If you want the exact look, you have to invoke those expensive tools and programs. Otherwise some of it may be possible to fake using layers upon layers and complex particle systems like Stardust, but even then it will be complicated and require long tweaking as well as long rendering due to massive amounts of particles and simulations. Such stuff simply isn't something where you push a button and it looks good.
It depends on how you are generating the particles. Some particle systems have walls that you can set up to make particle bounce, some have obstructions you can create with masks or the alpha channels of other layers. Sometimes you need two layers with particles so you can deflect the particles from one emitter in one direction and the other emitter in a different direction.
Please tell us what tools you are using and we can give you more advice. If you are fortunate enough to have Trapcode Particular you can do some amazing things.