npm - install dependencies for a package in a different folder?
You can use the npm install <folder> variant with the --prefix option. In your scenario the folder and prefix will be the same:
npm --prefix ./some_project install ./some_project
Update: Since the --prefix option exists, I now vote for @coudy's answer to this question. Original answer below:
No, npm will always install in the current directory or, with -g, in the system wide node_modules. You can kind of accomplish this with a subshell though, which won't affect your current directory:
(cd some_project && npm install)
The parentheses makes it run in a subshell.