If you want to try it, copy this code:
javascript:document.cookie="PREF= ID=ad93daafaa747f70:TM=1158373640:LM=1158374016:GM=1:S=wNuiLiKHrkRnMZtf; path=/; domain=.google.com"
go to google.com, paste it in the address bar, then go to the preferences and click "Save preferences".
If you want to go back to the original design, just delete your Google cookie.


{ Via Googlified. }
Related:
Other design experiments
User experience at Google