Rhubarb jelly is my vote-- A local fellow used to make and sell rhubarb jelly in my hometown and it was wonderful stuff, but I've never been able to find it anywhere else.

Most folks insist on complicating the flavour of rhubarb with other fruits, esp. strawberries. Don't do it! A little stem ginger is nice, but don't add anything that obscures or overwhelms the unique flavour.

Make a clear, rose-coloured rhubarb jelly. (If your rhubarb is quite green, don't use food colouring. Just shred a medium-sized beet into the jelly while it's cooking and strain the shreds out. It will be lovely on toast, scones, etc. and also makes a wonderful glaze for roast chicken or pork.