I'm not sure how I would use this for a game, but it only has 7 lines of code, and produces up to 1000 particles.
`Colorful bouncing 2D Particles, with only 7 lines of code
sync on:sync rate 64:dim P#(1000,3):do:MX=MouseX():MY=MouseY():X=MouseMoveX():Y=MouseMoveY()
if mouseclick()=1:for i = 0 to 5:inc Pt,1:if Pt>1000:Pt=0:endif:P#(Pt,0)=MX:P#(Pt,1)=MY
P#(Pt,2)=X+(rnd(500)-250)/50.0:P#(Pt,3)=Y+(rnd(500)-250)/50.0:next i:endif:for i = 0 to 1000
ink rgb(255-P#(i,1)/2,255,128),0:line P#(i,0),P#(i,1),P#(i,0)+P#(i,2),P#(i,1)+P#(i,3)
P#(i,0)=P#(i,0)+P#(i,2):P#(i,1)=P#(i,1)+P#(i,3):if P#(i,0)<=0:P#(i,2)=-P#(i,2)/1.2:endif
if P#(i,0)>=640:P#(i,2)=-P#(i,2)/1.2:endif:if P#(i,1)>=480:P#(i,3)=-P#(i,3)/1.2:endif
inc P#(i,3),1:next i:print "Press Esc to exit":sync : cls : loop
I like games, and stuff.