Phew! I eventually found links to the Orange PAYG animal plans... any good?
I've been on the Orange Dolphin from when it started. Originally you only got 100Mb data, I wanted to dabble a bit with the internet on my new smart phone at the time so it gave me a bit of usage to play with. They recently upped that to 1Gb, not enough if you watch videos all the time but good enough for simple web searches, email and occasional use of other apps like real time maps. I don't use the net much on my phone so it is a good package for me. I use it mainly because of the texts, 400 amply covers what I need. I top up then let the credit run down after the month is up before topping up again.
In case you don't know how the top ups work...
When you pay your top up you'll get a confirmation text and a 1 month period from that date in which to use the 1Gb data and 400 texts (with £10 top up). They normally remind you to top up again, a few days before the end of that month, as it is about to run out. When you do pass over the end of that month, or you exceed your allowances, any data and texts you use are then deducted from any credit you have on the phone until you top up again.
Dolphin Terms and Conditions.
You can top up larger amounts and get more data and texts. There used to be a £5 top up with less texts available, it seems to have disappeared since they upped the data allowance. You can also use it with magic numbers
to reduce call costs.
Hope this is helpful.