I'd planned a ride of about 25 miles yesterday, but I managed to twist my knee quite painfully on Saturday so that was off. Instead, I put some of the time to good use cleaning my tourer and MTB (which I've ridden a couple of times each this month).
I hosed down the frames and wheels and any other bits covered in mud/crud, using a stiff brush to get it all off, and wiped the chains and wheel rims with a rag. I left the bikes to drip dry briefly, and then sprayed the drive chains with GT85 to dispel water. Before I go out on each next time, I'll put a little TF2 oil on the chain. Only about half an hour in all, and time well spent.
I do a fuller clean of chains a couple of times a year, by taking them off (they have quick links) and soaking/cleaning in white spirit.
I never buy fancy cleaning products - if I need soap, washing up liquid is fine. And I stock up on GT85 whenever Aldi is selling it cheap, or I get WD40 whenever it's going cheap at my local weekend market - I don't think I've ever paid more than £2 for a 400ml can.