hey hey

i just put some floating up bubbles in a watertank that i was building for my scene. since my tank was cylinderical i just used a nurbs circle that was some what smaller than the tank itself since i wanted the bubbles to spread out instead of just going straight up. what i did was emit from object under the particle menu, changed the settings so that the direction was 1 in Y therefore the particles would go up. i also set the SPREAD to something like .500. also played with speed, particle/sec, life range, etc. etc. to get the desired effect.

depending on your situation you might want to try drawing a curve since the particles emit from the points on the curve and just emit from object.

oh you also need to change the points to spheres in the render attributes tab (i think, cant remember off the top of my head) but its in there. adjust the radius, and a shader and boom!! there ya go rising bubbles

good luck

Kyle