Many startups accomplish the same thing via the performance review process. Equity is usually in a state of constant dilution, so each employee's total effecti

Many startups accomplish the same thing via the performance review process. Equity is usually in a state of constant dilution, so each employee's total effective slice the pie can be adjusted over time, to a certain extent, by giving them bigger or smaller supplemental grants. I suppose the events depicted in The Social Network could be considered an extreme case.