visine bottles, man! cut the tip halfway and its easy to suck liquids up into it. so, after you fll it once theres some space left, the trick is to squeeze it till theres no air left and only piss in it and then suck up the rest. then you can tape/glue/tie/whatever it to your inner leg and when you squeeze it it even comes out in a stream! you just gotta tape it so it faces down and out like where you would be peeing.

*wash it out first