Delextreme, now DX.com has really started posting a lot of electronics stuff lately. Programmers, bare chips, a lot of Arduino and STM32 stuff, a bunch of sensor boards, descretes, and packages of assorted descretes. I picked up the MPU6050 board, because I'm too lazy to make my own, also a Segger J-Link clone.
Just watch out with the descretes, a lot of things like resistors, capacitors, and leds are cheaper from someplace like Mouser/Digikey if you don't factor in the shipping. If you are ordering from Mouser/Digikey/Newark anyway, you should just throw in a bunch of various descretes rather than get the bundles from DX. At least price them out first.
Edit: also look at the packages of buttons, switches, USB connectors....
Breadboard power supply module $3.60
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HC-SR04 Ultrasonic Sensor $4 - Remember when these things were like $30
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