There is a new $1/1 Purell Coupon available (excludes trial size). I am excited about this coupon because this is one of those items on most back to school lists. This month there is also a coupon in the August Walgreens coupon booklet and you can use it to save $2 per bottle:
Purell 8oz Bottle $3.99 (reg price)
Use $1/1 Purell coupon
Use $1/1 Walgreens Aug IVC (exp 8/28/2010)
I would print the coupon now and wait for a sale before the coupon expires. The coupon expires 30 days from the time you print it.