[ye_river_xiv] motivated me to post this as a separate idea - it was inspired by the idea 'Polycarbonate Keys'.
Any objects in a mixture of diverse objects will sort themselves according to size and density. This is because of the gravitational pull and the proclivity of small objects to slip beneath larger objects. This is also why raisins 'swim' to the top of a cereals box, if shaken long enough.
If there is just one specific item, this mechanism can be used to let it float on top. If you routinely wish to retrieve many different articles, more vectors are needed: I propose three vectors, two of which i can name : gravity and magnetism; i'll call the other X, and am open to suggestions.
The vectors are orthogonal to each other. Gravity is already in place, and the magnetic vector i propose to produce by placing a magnetic sheet in the left side of the purse. X will run alon the length. This way, a big, magnetic, Xy object will work its way to the left, frontal, upper corner of the purse. Small, magnetic, and non-Xy will go Left, down and to the back. This way, at least 8 Objects (corners of a cube) can be differentiated, or, with well worked out dynamics, 26 (corners, sides and planes).
Electric Fields as a third Vector would be cool, but the required field strength would be much to high for safe wearing of the purse (might be a good thieves-deterrent, though)-- loonquawl, Apr 01 2009 2D - Gel http://en.wikipedia...imensional_SDS-PAGE [loonquawl, Apr 01 2009] 1-D original idea Polycarbonate_20keys [loonquawl, Apr 01 2009] YAY! I've spawned an idea!I think a catchier, and more descriptive title might improve things. That "Orthagonal vector" bit caught my attention in the anno. but maybe something about auto-sorting would be just as good.
Perhaps you could induce a suitably isolated static charge... assuming that the issue with an electric field is the current... I believe I once read that Amber was suitable for gathering together wool and such this way, apparently without significantly painful results.
A safety device to ensure that the charge was dissipated before one put a hand in the purse would likely be necessary. Then again, women put up with some pretty painful devices in the name of fashion, so if it were a designer purse, and an effective but nonlethal charge could be applied.
As it's nearly 3:00 AM, my enfeebled mind keeps repeatedly saying "Wouldn't capillary action work?" Somehow I doubt that it would, unless tubes of lipstick are actually capable of being pulled through tiny pores...-- ye_river_xiv, Apr 03 2009 Yup, the title is feeble. 'To run a gel' is common usage, so went with that, but ...-- loonquawl, Apr 03 2009 //'To run a gel' is common usage//Well, maybe with 1930's upper-class English pimps.-- coprocephalous, Apr 03 2009 Quite brutal pimps at that - the gel is laid, then filled, then run, and then either photographed or cut up, or both.-- loonquawl, Apr 03 2009 Electrophoresis and dielectrophoresis can get you two axes, but electrostatic attraction/repulsion isn't very strong. Maybe magnetophoresis and diamagnetophoresis?-- notexactly, Apr 11 2019 random, halfbakery