Toys'R'Us has been running a Clearance event for a couple of months now. It appears to be an in-store only otherwise I would have just posted a link. Up until last week it was okay. Then they updated the discount amounts.
Brown seems to be the predominant discount level for brick construction sets. Brown was 30% off but is now 50% off, which is a fairly steep discount. There are a few Lego items on Clearance but the majority seem to be Mega Bloks or Kre-O. As always YMMV as to what is actually on clearance in your area, if you even have a TRU nearby.