One of the most common reasons that a view’s index size can get very big is due to the sorting options on the columns. Following on from the discussion about large applications the other day I would guess that some of the databases mentioned have view indexes that account for over 50% of their real size. You can see this with the R5 & R6 administration client, just go to the files tab, find the database you want to examine and then rightclick on it and choose ‘Manage Views’.
But how do you make the indexes smaller…
Dec's Dom Blog 
If you discard indexes after x days, will all the possible indexes for a view be rebuilt when just one of them is accessed ?
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Something else that shouldn’t be overlooked is the fact that one flat view that’s sortable by column sort clicks can remove the need for a multitude of other views. Especially when the users/specifiers of the application don’t yet know which implementations of view sorts will be of most value to them…
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