Who says that sausages don't grow on trees?
The blue sausages you see are indeed edible! Open one up and you will find lots of large black seeds covered in slimy flesh. My favourite way to eat them is to open the pod like a broad bean and take a mouthful of flesh and seeds, then spit out the seeds, which are very hard. The flesh has a sweet and delicate flavour, it reminds me a little of watermelon. It is more of a novelty fruit than a staple crop but it makes a fascinating and beautiful little tree.
I feasted on lots of blue sausages at the Plants for a Future sight in Cornwall. They're ripe in September, and the tree is often heavy with fruit. I saved the seed and have germinated many little seedlings in July - they are 10-15cm tall now and have done really well given the short growing season I gave them.
This tree grows quickly up to about 4m x 4m, sometimes it can also form a shrub. They are easy to grow, being very hardy, but need a moist soil with reasonable drainage. It's better to offer them a little shade and compromise fruiting than to allow the ground to dry out in full sun.
If you're interested in growing the blue sausage tree, I'd be really happy to provide you with seedlings. I have grown them in root trainers so they should grow away really well. Probably best to plant them outside after the last expected frosts though, as they're still very young.
As always I'd be delighted to swap a plant with you, or for a small sum of your choice! They're self fertile so you only need one tree.