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UK suppliers and part numbers for a standalone Arduino on breadboard or stripboard (veroboard)

PartValueDesc.MaplinsCost £BitsboxCost £
C110μFMiniature 7mm Radial Electrolytic Capacitor 10μF 50VVH08J0.12Bitsbox0.06
C21μFMiniature 7mm Radial Electrolytic Capacitor 1uF 63VVH03D0.12Bitsbox0.06
C322pFMetallised Ceramic Plate Capacitor 22pFWX48C0.13Bitsbox0.05
C422pFMetallised Ceramic Plate Capacitor 22pFWX48C0.13Bitsbox0.05
IC478051A Positive Fixed Voltage Regulator 7805 Value BrandCH35Q0.63Bitsbox0.25
Q116MHzCrystal 16MHz U4RR89W1.19Bitsbox0.45

PartValueDesc.BitsboxCost £
IC2MEGA168-PAtmel ATMega168-20PU 28 pin DIPBitsbox3.38

Another list by noob (all parts from bitsbox.co.uk):

See here for details: http://www.instructables.com/id/Stripboard-Arduino/

1x Atmel ATMega168 = £3.20
1x Stripboard = 72p
1x 7805 Voltage regulator = 26p
2x LEDs = 16p
2x 220 Ohm resistors = 8p
1x 10k Ohm resistor = 4p
2x 10 uF capacitors = 12p
1x 16 MHz clock crystal = 45p
2x 22 pF capacitors = 10p
2x .1 mfd capacitors = 10p
1x small momentary button = 18p
Total = £6.49

Optional extras

Header Strip = 26p (for 36)

Single Row Sockets = 56p (for 25)

24-pin DIL sockets = 16p

PP3 Battery Clip = 15p