Textbox Drag/Drop in WPF
http://www.codeproject.com/Articles/42696/Textbox-Drag-Drop-in-WPF.aspx

Odyssey RibbonBar
http://www.codeproject.com/KB/WPF/OdysseyRibbonBar.aspx

XPlorerBar: A WPF Windows XP Style Explorer Bar Control
http://www.codeproject.com/KB/WPF/XPlorerBar.aspx

WPF NotifyIcon
http://www.codeproject.com/KB/WPF/wpf_notifyicon.aspx

XPlorerBar : Part 2 - Adding design-time support to the WPF explorer bar control

http://www.codeproject.com/KB/WPF/XPlorerBar2.aspx

A WPF Pie Chart with Data Binding Support
http://www.codeproject.com/KB/WPF/PieChartDataBinding.aspx

WPF Image Pixel Color Picker Element

http://www.codeproject.com/KB/WPF/ImageColorPicker.aspx

Stacked Geometry Brush Factory
http://www.codeproject.com/KB/WPF/StackedGeometry.aspx

WPF Drag-and-Drop Smorgasbord

http://www.codeproject.com/KB/WPF/WpfDragAndDropSmorgasbord.aspx 

A Simple Color Picker With Preview
http://www.codeproject.com/KB/WPF/WPFColorPicker.aspx

Drag and Drop Items in a WPF ListView
http://www.codeproject.com/KB/WPF/ListViewDragDropManager.aspx

Quick and Dirty (but nice!) ToolTips via Markup Extensions
http://www.codeproject.com/Articles/36448/Quick-and-Dirty-but-nice-ToolTips-via-Markup-Exten.aspx

WPF DataGrid Practical Examples
http://www.codeproject.com/KB/WPF/WPFDataGridExamples.aspx

Selection made better
http://www.codeproject.com/KB/WPF/WPFComboList.aspx

Working with Checkboxes in the WPF TreeView
http://www.cnblogs.com/timy/admin/EditPosts.aspx?postid=1603339

A Versatile TreeView for WPF
http://www.codeproject.com/KB/WPF/versatile_treeview.aspx

WPF Interactive Image Cropping Control
http://www.codeproject.com/KB/WPF/ImageCropper.aspx

WPF OutlookBar Control
http://www.codeproject.com/KB/WPF/WPFOutlookBar.aspx

Quick and Simple WPF Month-view Calendar

http://www.codeproject.com/KB/WPF/Quick_WPf_MonthView_Cal.aspx

An Extended and Improved Version of the CodeBox with Line Numbers

http://www.codeproject.com/KB/WPF/CodeBox2.aspx

Developing an Autofilter ListView

http://www.codeproject.com/KB/WPF/AutoFilterListView.aspx

Custom TreeView Layout in WPF

http://www.codeproject.com/KB/WPF/CustomTreeViewLayout.aspx

WPF Squeeze TabPanel

http://www.codeproject.com/KB/WPF/WpfSqueezeTabPanel.aspx

Creating the Microsoft Outlook Appointment View in WPF

http://www.codeproject.com/KB/WPF/OutlookWpfCalendarPart1.aspx

WPF Taskbar Notifier - A WPF Taskbar Notification Window

http://www.codeproject.com/KB/WPF/WPF_TaskbarNotifier.aspx

Auto-filter for Microsoft WPF DataGrid

http://www.codeproject.com/KB/WPF/wpffiltering.aspx

Farsi Library FX

http://www.codeproject.com/KB/WPF/FarsiLibraryFX.aspx

WPF C# Ribbon Control Library

http://www.codeproject.com/KB/WPF/ribboncontrol.aspx

WPF Filename To Icon Converter

http://www.codeproject.com/KB/WPF/filetoiconconverter.aspx

Validizor - A Validation Control for WPF

http://www.codeproject.com/KB/WPF/Validizor.aspx

An Extended WPF TabControl

http://www.codeproject.com/KB/WPF/WpfTabControl.aspx

WPF Controls - A Visual Quick Start

http://www.codeproject.com/KB/WPF/WPFControlsQS.aspx

Understanding the default controls available in .NET/WPF can save you a lot of time.

Example 1	Example 2	Example 3

Editable TextBlock in WPF for In-place Editing
http://www.codeproject.com/KB/WPF/editabletextblock.aspx

A Customizable WPF TaskDialog

http://www.codeproject.com/KB/WPF/TaskDialog.aspx

A Generalised WPF Wizard / Procedure Dialog

http://www.codeproject.com/KB/WPF/PolarPanel.aspx

WPFDesigner

http://www.codeproject.com/KB/WPF/WPFDesigner.aspx

WPF Autocomplete Textbox Control

http://www.codeproject.com/KB/WPF/WPFAutoCompleteTextbox.aspx

WPF ProgressBar

http://www.codeproject.com/KB/WPF/WpfProgressBar.aspx

WPF AutoComplete Folder TextBox

http://www.codeproject.com/KB/WPF/autocomplete-textbox.aspx

Wpf ErrorProvider - Integrating IDataErrorInfo, WPF, and the Validation Application Block (VAB)

http://www.codeproject.com/KB/WPF/WpfVABErrorProvider.aspx

WPF Html supported TextBlock

http://www.codeproject.com/KB/WPF/htmltextblock.aspx

Wpf Drag & Drop behaviour

http://www.codeproject.com/Articles/39191/Wpf-Drag-Drop-behaviour.aspx