Change icon size in unity's application switcher (alt-tab)?

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http://askubuntu.com – When I switch applications with alt-tab under Unity (full version, not the 2d one), my open applications are displayed, represented by their respective icon. These icons are quite huge... everytime I hit alt-tab I'm a bit surprised by the thing that pops in my screen. I'd prefer a much smaller icon size.. is there a way to change this somewhere? They seem to be ~96x96, I'd aim for 48x48 :) (HowTos)