I'm currently in a charity knitting phase, after the challenge of Uncia. I thought a batch of fingerless mitts might be of use, so these will be going to Knit for Peace. I prefer full mittens, if it is cold enough to make mittens necessary, but fingerless seem to be the style du jour.
I have made a few pairs of Newfoundland Mittens in my time, using the free pattern published by Creative Whimsy, or sort of. I love them. The pattern consists of knitting two rows of the main colour and then four rows of the contrast - four stitches contrast, slip two main stitches and repeat. This creates a honeycomb web effect which looks far more complex than it is, since you are only really using one colour per row.
You may have noticed that there are two variants of the pattern As with many things in knitting this is a very simple change. After the four rows of contrast there are two rows of main colour. If you purl the first of these two rows you get a row of colour change bumps.
If you knit both rows the effect of the web of main colour is more dominant. I prefer this effect, which is why I have knit it more often.
I've also used small oddment of J&S 2-ply jumper weight and other tweedy bits knit double, changing the yarn for each 4-row repeat. It is possible to achieve quite a painterly effect by doing this.