Well, here in Mexico we always eat, it is always ritual to have the "mother" cook a lot of food and invite several friends and family over, (the family almost never goes in full, but those that go are cousins of the same age and their parents) there is beer and one (or several, deppending on the tastes of te family) bottles of alcohol, if the party is for Kids, well... better said 15 yo and under, there is always a Piñata wich gets beaten to death and the candys fall to all the Kids, if there are Kids of all ages, there are 2 Piñatas (one for the little Kids and another one for the Big Kids) and in some not so rare cases there are 3 piñatas (the last one for the Adults)... i remember in my 18th birthday i bought a Piñata and filled it with condoms and little plastic bottles of alcohol, also some bottles of flavored lubricant and other things like that (popsicles shaped as "you know what" etc)
its kind of funny but having a Piñata party is really great, even more when everyone is half drunk and you give him a pole, cover his eyes, spin him aroud the amount of years he has had and trow him thowards the piñata hopeing he doesnt hit someone in the head... good times, good times
OOOH!!! there are several diferent traditions, some times it is also a tradition to have instead of the "mother" cooking, we buy a bunch of meat, prepare several sauces, Guacamole, buy tortillas and just preaty much grill everything we have, also, me and my friends have this tradition of kicking the birthday one in the butt the amount of years he haves, we go in one by one kicking the birthday boy 23 times in the butt each, we are 5 close friends who do that, and it is funny because some remember how hard we kicked them in their birthday, so there can be some really interesting conversations...
-ok, are you ready??-
-not so hard!!!-
-Dont worry, i will kick you as easy as you kicked me in my birthday-
-oh, ok... wait what??? UUUGGGHhhh-
HAHAHHAHAHA oooooh, good times