Thu 2010-09-30 
A cracked old mushroom, probably a bolete of some sort, judging by the pores on its underside.
Photo taken in The Wilderness, Whiteknights Park, Reading University grounds, Reading, UK, on 2010-09-21.
Tristram Brelstaff
Possibly the sepia bolete, Boletus porosporus (= Xerocomus porosporus).
Wed 2010-09-29 
From early summer: a common swift moth, Korscheltellus lupulina = Hepialus lupulinus (Lepidoptera: Hepialidae).
Photo taken in Whiteknights Park, Reading University grounds, Reading, UK, on 2010-06-06.
Tue 2010-09-28 
From earlier this month: a frit fly, probably a Thaumatomyia sp. (Diptera: Chloropidae). The following is another from back in spring time:
Photos taken in Whiteknights Park, Reading University grounds, Reading, UK, on 2010-09-12 (upper) and 2010-05-04 (lower).
Mon 2010-09-27 
What I think is a Lauxaniid fly, possibly species Minettia fasciata (Diptera: Lauxaniidae). However, this thread at diptera.info suggests that M. fasciata is rather difficult to identify unambiguously, so it might be safer to follow Paul Beuk and just assign it to the Minettia fasciata group.
The pale abdomen of the above specimen suggests it is a female (compare with the male and female in this photo). The specimen below, which has a grey abdomen, is therefore probably a male.
Photos taken in Whiteknights Park, Reading University grounds, Reading, UK, on 2010-07-18 (upper) and 2010-07-07 (lower).
Sun 2010-09-26 
A dung fly, probably Scathophaga stercoraria (Diptera: Scathophagidae).
Photo taken behind Hangingstone, near Guisborough, North Yorkshire, UK, on 2010-08-08.
