I've got a nice acrylic hood on my Replicator (http://www.thingiverse.com/thing:23386) that keeps it nice and toasty inside, but I was wondering how much. This clip mounts an Acurite meter inside the Replicator build area. It mounts to the inside of the back panel, just like the spool holders mount on the back, using the cutout that is/was/maybe intended for a nozzle wiper.
UPDATED: 6/24/12 The original was too 'bouncy'. It's been updated to remove the flex.
Printed perfectly at full acceleration with 0.27 layer height, 100% infill.
The meter is available at Amazon here: http://www.amazon.com/Acu-Rite-Indoor-Humidity-Monitor/dp/B0013BKDO8/ref=pd_bxgy_hg_img_b Other meters could probably be made to fit, but the clip on the back of this one fits the mounting clip perfectly.
You will need to break out the cutout in the back panel. I'd suggest drilling the corners to avoid splitting.
And yes, it does clear the carriage, by about a quarter inch. During a build, the temp inside goes above 115 degF, and the humidity drops by at least 10%.