The guide books call them "chicken busses", but the only chicken I've ever seen on board was fried and in a convenient cardboard takeout box. Whether you're going across town or across the country, these repurposed school busses (and for the very lucky, some old long haul coaches) will get you where you're going for under a couple of bucks.
I've always rather taken the bus than a cab, and here in El Salvador there's good reason. The busses are reasonably convenient - there were a couple of ways to get to San Salvador or closer Zacatecoluca from our location, and depending on the route, the particular busero and the phases of the moon it would cost between a buck and $1.50. Within San Salvador, the bus cost us a cora (25¢) each, but I think the actual fare was less.
And the cost effectiveness is only a part of the charm. Local vendors get on the busses at random stops and rotate through constantly while waiting at the terminal. Among other things, you can buy hot pupusas, sewing supplies, ice cream cones, fresh fruit and veggies, candies, knives and, of course, chicken (though I only ever saw the chicken at the Terminal Sur in San Salvador).
There's a somewhat complex system for riding the intercity busses - there's at least two guys running the bus, usually three. One guy drives, and the rest hustle people on the street to get them to ride the bus, take the money and help finding seats and moving packages around.
It's especially crazy near the bus terminals, as the buseros are trying to get you on their bus, seemly regardless of where you actually want to go. But, unlike some taxi drivers, they do take no for an answer, even if they look at you like you just made a terrible error when they drive off, clinging wildly to the aftermarket grabrails around the door.
But, the best part of the busses is their elaborate decoration. Each bus appears to belong to one driver or crew, and they personalize the hell out of it. Most busses have elaborately airbrushed names on the inside and outside of the body: names of family members, the buseros themselves or the name of the bus - no one knows.
One of our regular rides was covered in stuffed animals hanging from the ceiling in front of the windshield. In a particular bit of oddness, one was a cuddly version of Winnie-the-Pooh being devoured by Eeyore (or it was Pooh in an Eeyore suit - either way, it was strange). Many show their allegiance to their favourite soccer team with vigour. Many Salvadoreños are, like us, fans of the Spanish Primera Liga, so we were often careful on the Real Madrid busses in case our Barça gear got us in trouble. But, thankfully, our team is equally well represented.