Elementary S01E09

S01E09 - You Do It to Yourself

Security cameras that are disguised as fire detectors really do exist. A Google search provides Alibaba as first link: http://www.alibaba.com/showroom/fire-alarm-hidden-camera.html
I wasn't able to find the exact model they used in the show, though.

Screenshot taken at ~12:20

Later, at ~29:45, Holmes sits in front of a disassembled Computer (from what I can tell an iMac):

Holmes in front of a disassembled iMac.

He apparently tried to recover deleted videos from it. Holmes, surrounded by the computer parts, makes for a nice picture, but that was complete overkill: just extracting the harddrive would have been enough (as a first step).
Then he should have made a low-level copy of the disc (under Linux he would have used for example dd), so that he would not accidentally destroy the original data. All further operations would have been done on the copy.
In fact, Holmes would have had a pretty good chance to recover some data (and most likely the videos). It's relatively expensive (time-wise) to fully erase files on drives. Operating systems therefore just shortcut the actual deletion operation by marking used space as free, without overriding (or clearing) the used space. Specialized programs can run over the drive and search for anything that looks like a video. Given that videos are very big there, it is unlikely that the operating system has already overridden all previously used space.
There are lots of programs that can help recover deleted data. I would have probably started with PhotoRec (a free open-source program). If you have other good suggestions (especially open-source) please add them in the comments.

In this episode there is then one last computer reference at ~37:50: a Microsoft Surface.

Microsoft Surface

Microsoft has been doing a lot of ads for the Surface, and this product placement is not really surprising. MS, for example, also made the Surface the official tablet for the NFL. It seems that the announcers didn't remember its name, though :) microsoft-surface-at-nfl-games-described-as-ipad-like.