C#

1. Enable theming in your app (which binds to comctl32 version 6).
2. Read the icons and remove the alpha pixels. It's not as simple as it sounds, though. You have to also use an unsafe context for optimal performance. Christian Graus here on CP has several good articles about image manipulation.

-Nick Parker
DeveloperNotes.com

protected override OnClick(EventArgs e)
{
  if (this.Parent == null) return;
  foreach (Control c in this.Parent.Controls)
    if (c is RadioLabel && ((RadioLabel)c).Group == this.Group)
      // Easy-to-property like RadioButtons have, and also draws or remove
      // the border like A.Wegierski mentioned (if you did it that way).
      ((RadioLabel)c).Selected = c == this;
}

public GroupCollection Group
{
  get { return this.group; }
  set
  {
    // Remove this control from the group, even if null is assigned
    // (easy way to remove a RadioLabel (or whatever) from its group).
    if (this.group != null) this.group.Remove(this);
    // Assign the group and, if not null, add this control to it.
    this.group = value;
    if (this.group != null) this.group.Add(this);
  }
}

private TabPage GetTabPageFromPoint(Point p)
{
  // If the X and Y coordinates from the drag-drop operation are still in
  // screen coordinates, don't forget to translate them:
  p = this.tabControl1.PointToClient(p);
  for (int i=0; i<this.tabControl1.TabPages; i++)
  {
    Rectangle rect = this.tabControl1.GetTabRect(i);
    if (rect.Contains(p)) return this.tabControl1.TabPages[i];
  }
  return null;
}