When posting near a Tuesday, remember that a several hours will be wasted on server downtime. This can be worse if there is a patch, even a small one.
On the other hand, this is an excellent time to bid on auctions. The bid price is usually much less than the buyout price. That means that if you're in no rush, bids are much cheaper. They can tick away while the servers are down, when no one can outbid you. Keep in mind this isn't an uncommon tactic, so unless you're close to the downtime, you're likely to be outbid, meaning you wasted your time.