This takes me back. My dad worked for IBM and had access to many broken thinkpads (mostly broken displays) so he would bring them home for me to tinker but in the end I installed debian on them, installed ISPconfig and rented out webspace from the laptops running under my bed.
Laptops are awesome for servers since they have built in UPS's and are not very power hungry
It was a fun experience and got me started on my road to becoming a MSP