UKDistributedView and UKFinderIconCell provides a very flexible icon view. 
More precisely, UKDistributedView is an NSTableView-like class that allows 
arbitrary positioning of evenly-sized items. This is intended for things 
like the Workspace/Finder's "icon view", and even lets you snap items to a 
grid in various ways, reorder them etc. Finally it can handle several 
thousand of items smoothly.

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