In share point you can add any feature as your wish,through a webpart.
(1) Create a website using VS
(2) Add a webuser control into it
(3) Add your logic into usercontrol functions
(4) Copy the .ascx & .cs file
(5) Paste in a separate folder
(6) Create a class library
(7) Add the System.Web reference
(8) Inherit from "UI.WebControls.Webpart"
(9) Write code to load the usercontrol in class library
(10)Build it
(11)Add the .dll into bin of virtual directory
(12)Add safe control in the web.config
(13)Go to the sharepoint site & Populate it
(14)Add that webpart into your page
(15) :)