If you have a Tatonka or a Trangia then here's a few tips that might help you get a bit more out of your stove.
1. Get more heat out it - by using a wick sitting inside the burner well (see the images below of my Tatonka) you can get a faster cook time. The larger flame in the first image is using the wick which produces a bigger flame if you need more heat or a faster cook.
With the wick I use, which is made from carbon cloth so it does not burn away, I can boil 1 pint of water in a Stainless Steel caddie in 10 mins vs. 16 minutes without the wick. The wick is next to the burner in the 3rd image.
Yes it uses fuel faster but it gives you additional versatility when you need it. More applicable to cooking than boiling water but the comparison acts as an illustration.
2. Get a better grip on the cap - Wrap a couple of elastic bands around the outside of the cap to give you a better grip when twisting the lid on or off.
3. Leaky cap/seal ? - got a leaky cap, try making an 'O' ring with a piece of small diameter bungee cord and pop that in the top of the cap first and then sit the proper seal on top of that. it brings the seal closer to the burner ring and helps produce a better seal.
4. Ease a sticking cap - my Tatonka has a 'gritty' feel when tightening up the cap so I put some Vaseline on the thread on the INSIDE of the cap. Don't put it on the outside of the threads on the burner, it will burn off first time you use it.
Happy cooking.... Paul