I recently purchased one of these:

Very bright light, but doesn't look like it is going to winter well.

Anyone bothered to adjust them (or other lights) to make them more winter proof?

Sellotape 'round the join.
It works.

Damn, was hoping for something far more techy.

stick it in a condom and tie a knot in the bottom

Ti29er
+1

smear vaseline or grease round all the seals, then wipe off residue.

Sellotape is pish – its neither stretchy to give a good seal or waterproof.

Good quality translucent silicone sealant if you think its that pants – but I have always broken or lost lights before they get waterlogged

TJ +1

Sellotape 'round the join.

Under-engineered

Good quality translucent silicone sealant

Typically over-engineered!

Electricians tape – somewhere in the middle and perfectly good.

Most of mine (that did not fall off on the trails) have the Sellotape option & work just fine.
No need to spend £ when you don't need to.

"Good quality translucent silicone sealant"
Typically over-engineered!

Fair point – I don't normally bother with using translucent stuff. Definitely the right way to do the job properly though (it's amazing what you can make IP7 with it!)

I use self-amalgamating tape on mine – it's designed to waterproof joints

It's not in anyway transparent though so won't suit all lights