Last night, I hit a wall with the Arduino.  Specifically, I ran out of memory.  Yeah, I know, I've got a lot going on; the real time clock, the SD card, the LCD shield, I'd like to post to Twitter, the temp/humidity sensor, some buttons, etc.  Anyway, this all came crashing down last night when the Arduino IDE delightedly told me that I was out of space.

A little digging later, and it looks like I'll be losing the SD card functionality, and maybe the RTC.  My thought process is that I can use Twitter for my data logging and repository, and that will include a time stamp on the tweet.  I can use the millis() functionality for my timing, as I don't think I'll be running any given program for more than 48 days.  I was just hoping to have something a little more refined, with time stamps and an SD card file that I could dump to a local device when I hit the IP address of the board.  Yes, I know I could get a Mega up and running (and I even have one laying around), but that would require a lot of rework and rethinking.  For the moment, just eliminating some non-necessary functionality is the way I'm probably going to go.