Is there any usage preference between artifact and artefact?
My understanding was that an artifact was properly applied to physical, historical objects, while an artefact was more correct for more abstract, intangible, error-ish concepts, for example a compression artefact.
However, the couple of online sources I checked suggested that the difference was merely spelling, and that both were usable for both definitions.
Best Answer
The only usage preference I'm aware of is that artefact is preferred in British English and artifact is preferred in US English, but that both are acceptable in either case.
See the Oxford Dictionary, for example.
Personally, I tend to mix them the same way you do: I collect artifacts in Tomb Raider and my compressed photos have artefacts!