One thing to keep in mind if you're out with a group of friends and want to buy a round of shots for everyone is the cost. They may be short and gone in a split second, but we're not talking $1 or $2 a drink here. Bars would lose so much money if they dispensed liquor at those prices on a regular basis. Depending on where you're at, shooters can cost around $3-5 each and if you order a round for 10 people that is $30-50, not bad but it can be more than some people are expecting. To avoid an extra surprise, don't order rounds on a tab unless you have a credit card (which many bars now require to run a tab). I've seen parties get a little crazy and run up a $200-300 tab on shots alone (that's about 5 rounds for those 10 people). Let's just say they were at a point where they were oblivious to the total until the credit card statement came in.
Shots are fun, especially in a crowd, but it is easy to get carried away with them. In reality one or two is enough for anyone on a given night considering you're probably drinking something else as well. Keep in mind that summer is prime time for drunk drivers and you don't want to be one of those. Also, have your hangover cures ready just in case.