The logs is a different story. Stacked them in the winter, and apparently little bugs burry their eggs in these things.

So when the temperature in the livingroom went up, these bastards thought it was spring and came out of the logs. Sigh.
Beware, if you have old untreated wood in the house, as the "little Bastards" you refer to are woodworm, most likely Anobium Punctatum (the Common Furniture Beetle - CFB, tiny round hole 1-2mm) or possibly woodwasps (larger oval exit hole 3-5mm, harmless). Outside chance of Wood boring Weevil (cant remember latin name but no real threat) or the good old Deathwatch beetle (Xestovium Rufovilosum - larger round hole 4-5mm - strange clicking sound in the night, thus the name).
All wood boring beetles tend to have a similar cycle. Eggs laid in the grain of the wood, larvae, when born, feeds on the wood by boring into the timber, then pupates, beetle hatches around spring time (late Feb to end of April) then bores straight to the surface giving a nice clean exit hole.
The powder left behind it packed tightly in the exit tunnels (called Frazz) and can work loose when the timber is knocked. Existance of frazz is not proof that you have an active infestation (frazz can stay in the holes for years after the beetle has emerged and is often used as 'proof' that you have an infestation thus 'you need us to come and spray your house, honest Guv'). The existence of exit holes in spring, and seeing the little B's in your house is definitley proof that you do.
Ooh that takes me back a few years