Vandalon

Vandalon (Ganglais) started as the simplest imaginable exercise: spend some month creating a fully* Germanic Frenchlang to study how linguistics work, before switching back to the "serious" a-priori stuff for my sci-fi conworld. The rules were as simple as restrictive: Modern French phonology. No exceptions. No Greek or Latin loanwords - Germanic roots for everything (this rule was later amended by incorporation of pre-Indo-European loanwords). Pedantry follows Aesthetics - derivation rules are there to create a feeling, not to follow actual historic pattern. What should have been a few week's exercise became a life's project. I've never returned to "serious" stuff - instead, I came to consider it boringly arbitrary and uninventive. Nor did I return to that sci-fi setting. Instead, a heterotopia closely resembling yet drastically different from actual humanity's history evolved around it, full of languages based on similar idea.