Never forget your laptop at home (or at work!) again! The ultimate briefcase / laptop bag for the sophisticated and discerning professional!

Background:

At many companies, employees take a laptop to/from work every day.

In the past, laptops were heavy enough that it would be incredibly obvious whether a laptop was in a bag or not.

The issue:

Modern laptops are light enough that it is possible to take a laptop bag (Figure 1) to work without realizing that there is no laptop inside. This can be an annoying and time-consuming mistake.

***Fig. 1:*** *The briefcase shown here could easily weigh 5 pounds without a laptop inside, so it may not be immediately obvious whether or not a one-pound laptop is present inside or not.*

Proposal:

Proposed here is a laptop bag that makes it unavoidably obvious that there is no laptop inside. The model shown in Figure 2 pops up a spring-powered flag whenever a laptop is not present.

***Fig. 2:*** The high-visibility **“Pack your laptop!”** reminder flag (A) at left protrudes from the bag when the laptop compartment is empty. A proposed mechanism is shown at right: the flag is attached to a “laptop cradle'” (B) that is supported by several springs (C). When the laptop is placed in the bag, its weight compresses the springs and pushes down the cradle-and-flag mechanism.

The flag-based approach described above makes it incredibly obvious if a laptop is not present. It also has the advantage of being easily overridden by a user who is intentionally not packing their laptop: they can simply press down on the flag while zipping the bag’s laptop compartment.

Rejected simpler Idea:

One could imagine a laptop bag with a transparent panel that would allow visual confirmation of the presence/absence of a laptop. Although this would work (and requires no moving parts), it would still be easy to grab the bag in a rush without realizing that the laptop was missing. Additionally, it has the disadvantage of advertising the presence of a (highly-stealable) laptop to fellow commuters.

Tactile alternative to the “flag” idea:

For a briefcase, the handle could change texture when the laptop is present. For example, dozens of metal spikes could protrude from the handle until a laptop weighed down the laptop cradle, at which point the spikes would retract into the handle, like they were part of some kind of Indiana-Jones-style ancient temple trap. (This could be all done mechanically, with no need for electronics, using cables that connected the handle to the laptop cradle.)

Conclusion:

You should crowdfund a laptop bag like this right now! If you are successful, it will prove that a market exists, and hundreds of much-cheaper knockoffs will flood the market before your initial prototypes are even done!

PROS: Never forget your laptop again!

CONS: Any object that is similar in shape to a notebook computer (e.g. an actual notebook) would cause false positives.