Pegtop common components includes the most flexible color gradient class available for Delphi.
Of course the are many VCL components making use of color gradients, too, like panels, a gradient editing dialog and many more.
Then there are a couple of file dialogs, based on TOpenDialog, extending the good old file dialogs a bit.
TPegtopTrackBar and other slide bars is another component you don't want to miss
if you are searching for a way to let the user adjust a value easily without entering a number
(which also can be done, because the track bar allows the user to open a numeric edit box, which also can be used separately).
There are much more components and useful classes included to this package.
Download the compiled demo to see what's possible.