Nutcrafter nut cheeses are excellent (and I'm pretty sure soya/gluten free) but not sure how easy they are to get outside vegan fairs/ festivals (they sell them in my local health food shop but that's because they are made locally). They are also expensive at £8-£11 but the black ash is absolutely to die for, everyone I know who has tried it go nuts for it (no pun intended!)
Also locally we have sgaia mheats which are seitan based burgers and steaks and are fab.
Drinking alpro chocolate soya milk just now which is a lovely treat :)
Vegan Supermarket Finds (UK) group on Facebook is good for finding accidentally vegan stuff.
The Free From cornetto cones in Tesco are lovely. Also from Tesco I like the caramel chocolates (made by choices). for sweets goody good stuff do nice cola bottles etc.
Not sure if everyone knows this but the cheese in Tesco/ Sainsbury's is made by sheese so if you don't like one you won't like the other. For my part I don't like cheddar sheese or plain cheddar spread at all but I like the Wensleydale with cranberries, the Greek style and I love the sweet chilli spread. Sheese usually give out loads of free samples at vegan festivals so a good place to try out the different kinds.
I get the vegan kind box too and I love that every month I get to try a few new vegan goodies. Some of my favourite have been ten acre cheese and onion crisps and these little microwave cakes where you just add vegan marg and water.
Raspberry ruffles are good too. I'm a huge crisp addict and love walkers prawn cocktail and salt and vinegar, bacon crispies from coop, Texas bbq pringles, skips, sweet chilli sun bites- lots out there as well as the fail safe ready salted.
Sorry got a bit excited there :) vegan for 8 years love finding new products (and I do eat a very whole foods, fruit and veg based diet but the occasional processed treats are fun!)