Contents: one Arduino Pro Mini 5v; one RFM12B, slightly modified; one compiled program; two AcuRite temperature sensors.

A first draft of the code is published:

https://github.com/JorjBauer/acurite_decoder

which happily spits garbage like this out the serial port:

[AcuRite decoder]
addData: A2 66 44 90 88 93 F7
DecodePacket: A2 66 44 90 88 93 F7
Source ID: 4454
Channel: B
Humidity: 16%
Temperature: 4.40 C (39.92 F)
addData: C2 7E 44 FF 9 81 D
DecodePacket: C2 7E 44 FF 9 81 D
Source ID: 382
Channel: A
Temperature: 15.40 C (59.72 F)