So this low level play nonsense from the other week has been rattling around in my head and gave me an idea. This idea is only really useful in a situation where you want the characters to start off prior to being adventurer types. Like if you want to start them off as Tom Bucktooth with a pitchfork or some such and you want to kind of develop their background through play.
Every character starts as something other than an adventurer, perhaps your Fighter began life as a dogawfully strong farmhand or the implacable and untiring blacksmith apprentice. Mayhap your Cleric started out as a clerk in a temple and your Wizard as an accountant. Anyway, even the mightiest of heroes and villains began play as something other than what they ended up us, they were all a 0 level character somewhere in their background.
My thought was that the base classes of d20 Modern would work perfectly to represent 0 level characters. The classes are vague and unfocused enough that they don't have any iconic abilities like Fighter and Rogue or Cleric do, but they have enough ability to survive low level encounters without truly being as powerful as first level Pathfinder or 3.5 classes. The feats, talents, and initial skills they have access to can form the character's background and you can also turn classes like Fighter and Rogue into advanced classes accessible at like level three or so.
This little idea doesn't really do or change anything other than delay higher level class abilities, however, I think it might be kind of neat to use in a situation where the players are townsfolk and their town comes under attack or some such and it wouldn't make sense for them to already be Fighters and Clerics and such. Also, I like d20 Modern and its class system.