On Linux it is extremely easy do use rdiff-backup for local and remote incremental backups. When I work, I have a minutely cronjob for my work directory. For the whole system I have a hourly schedule. When I resume work the next day, the previous mess of diff files from the work rdiff target directory is deleted and a new clean "emergency" cycle is started. Losing one hour of great concentrated coding can be extremely annoying and hard to reproduce so this is a cheap way to prevent it. But I guess even an hourly backup would be a good first step for many people.

Remember, a harddisk probably costs less than one day of your work. Or just get an USB stick for the most important bits.