Timing is everything!

Bargains can be had purely by deciding the correct time to purchase things, a brief guide:

Airline Tickets - (On a Wednesday, approx 21 days before your flight)
Airlines make major pricing changes every week, typically on Tuesday evenings and Wednesday mornings. About 3 weeks from your flight, you'll see plenty of deals out there as airlines scramble to fill seats. Don't wait much longer, she cautions; prices jump significantly from 14 to seven days ahead of departure.

Champagne - (December)
Most people assume that because everyone wants a good bottle of Champagne for New Year's Eve that prices go up during the holidays. But due to fierce competition among the Champagne houses, prices are actually lower during the Christmas holidays than they are at any other time of year.

Electronics & Gadgets - (After new model launches)
When the latest and greatest of a product is released, you'll often see prices drop on what had previously been the best thing out there.

Petrol - (Early Morning)
Most petrol companies adjust their prices between 10am and noon.

Wine - (Early Autumn)
For best selection, you can't beat the harvest season, that is when most vineyards release their latest vintages and all others are heavily discounted.