Definately some sort of maggot. In France they call them Vers Blanc, White Worms. There are loads of chemical remedies but our point of growing our own was to get away from self poisoning.
As for what I'm growing at the mo...
Radish (second attempt fingers crossed)
Black Radish (It's like black carrot thing - popular in France but I never saw it for sale in England
White Radish (as above but white

)
Parsnip
Swede
Salsify
Loads of beans
Tomatoes (It's great not needing a greenhouse)
Courgettes
Spuds
Celeriac
Every variety of the brasica I could find
Sweet corn
Pop corn - first attempt but we'll see how it goes
Various fruit bushes
Various melons
and Cape Gooseberry
That about all I can remember. Basically if I buy anything with seeds (oh yeah I forgot, various peppers and chilies) I keep them and plant them. All my tomatoes, strawberries etc started from a shop bought fruit.
Buy anyway, back to the maggots. In true, waste nothing style, I'm collecting them and catching some lovely trout!! Shame about the radishes though.