Import multiple vcf files into gmail

You can import contacts into gmail - it currently accepts csv files or vcf files. Unfortunately you can only upload one file at a time. If you are trying to import a full phone backup of hundreds of vcf files, that isn't useful. It turns out vcf's have their own internal structure and you can just combine them all into one giant file (using cat on linux):

cat *.vcf > ../allinone.vcf