Blutak would not work for this. If you have it in contact with body heat too long it gets ropey. It would constantly stick to your hands on contact.

I think OP was commenting that they're completely different things, with different purposes and uses. Blutack is great for sticking a poster to a wall, because its easy to put up and take off, and can be useable again. It is not for something to be permanent and used.

Yup. They're solving entirely different problems.

Sugru would be great but for the really short expiry as it's just the sort of thing I'd keep by indefinitely for an unplanned repair along with glue, tape and epoxy putty.

Blu-Tack doesn't harden, it stays sticky. It's used to attach posters to the wall and stuff like that. I wouldn't want to use it on the edge of a MacBook, it would just gather dust and grime, and would easily fall off.

If stuck to posters or wallpaper it also leaks oil/plasticizer over time (months to years) which is absorbed by the paper and causes staining. I discovered this the hard way in my late teens/early 20s.

Solution is to apply some Sellotape (Scotch tape) to the back of the poster first, then put the Blu-Tack on the plastic tape, which blocks the solvent. And avoid using it on wallpaper (emulsion or gloss paint is fine). Better still, use poster holders and a picture hook, or go the whole hog and frame your artwork properly.

Sugru ... air-cures: it doesn't have the solvent-leaching problem, but if you used it on a poster the only way to get the poster down would involve a chisel or sandpaper. Blu-Tak is for temporary attachments; Sugru is intended to be permanent.

It will also stain the wall and sometimes pull the paint off if left on for long enough.

I think they fixed it since but I recall my last MBP had a wicked sharp edge on it. I used a different trick though, the same one you do when you use tin snips. You can burnish a sharp edge on metal objects. I took a round screwdriver handle and rubbed it on the edge at a 45° angle and it was gone.

Oops, I meant screwdriver shaft not handle. That just tears up your screwdriver!

The sugru that's been in the fridge might be rock hard just because it's cold. If it warms up and is still hard, then it's no good.