Delphi components are one of the reasons that Delphi is such a popular programming environment. Using components is really easy and they are a great way of reusing you own code and that of third parties. Delphi components are also compatible with C++ Builder but not the other way round.
A software company that I used to associated with (First Internet Software House) has kindly allowed me to republish all of their Delphi and C++ Builder components, most come with full Delphi source code and some also contain the equivalent code in C++ for learning purposes. They have only been tried and tested using Delphi 5 but as each component includes full source code they shouldn't be too difficult to get working with Delphi 7 or later versions.
There will be about 6 components in total (all with source code), so to get started here goes
Spawn Command-line Processes Component
With this component you can spawn command-line processes and obtain the output from
them while they are running. The spawned process is invisible to the desktop and the
host application can terminate the process at any time. Complete with Delphi and C++ Builder source code.
Enable Group Component
GroupBox derivative that recursively enables/disables all children as well.
File Notification Component
This component creates a thread and uses it to monitor the contents of a directory
or directory tree. Many different file changes can be monitored such as file size,
last write, creation & deletion etc.
This C++ Builder and Delphi Component allows you to easily create a system wide hotkey.
NT Event Component
This non-visual component is a wrapper for the Windows NT event logging API.