About software reuse using code repository

Your question is as broad as a Chicagoan's shoulders. Code Reuse tools are a dime a dozen. You'll want to find one that fits into your particular environment, lest you find yourself controlled by, instead of in control of, your dev environment.

http://builder.com.com/5100-6387_14-5172029-1-1.html
^ This is a review of FMS's "Total .NET Developer Suite". I like it because it's scalable - from a few users, to an entire enterprise.

I can use it in my own small shop - and recommend it to big clients as well.