Most of my gadgets have been used until they go pffft or fall apart. They don't often get replaced, but some have been and some would be;
I don't miss the panini thing, the mini deep fat fryer or the food processor.
The old three tier steamer would probably be replaced immediately if I see one on offer with a removable bottom to the second tier, as that means I could cook a whole cauli in one (and would be used for a fuckton of veggies every day).
I've had three rice cookers. They were great for steaming potatoes with or without skins (to make the best mash ever when bunged through the potato ricer the OH is too daft to understand how to work it), cooking a load of perfect sushi rice, obviously, and for dealing with pasta/anything else when I had a kitchen with an entire two foot counter to work on.
I wouldn't miss the microwave. It's only used by the OH.
I miss the blender, but unless I get one costing more than twenty quid, it'll just get blown up by the OH.
I replaced the stick blender several times (going up in value when the OH started blowing up the cheap ones). Having it makes not having the blender tolerable.
I believe there's a giant coffee maker in the loft. An ex bought it for me one year when he was pissed. It was shit, as I don't drink milk and use cheap shit instant a cafetiere, it cost about £120 and the person who had actually wanted one was his sister, not me.
I live in hope that the cherry stoner attachment on the random kitchen tool in the drawer will ever see cherries from my tree instead of the cunting Wood Pigeons. I use the egg slicing thing for eggs and beetroot and playing like a mini harp when I'm bored doing the washing up.
I've made jam and completely forgotten the thermometer, but it's handy it's there.
The slow cooker does a great job on chicken, etc, whilst I can't afford to replace the oven (which has two temperatures - off and Hotter Than the Surface Of The Sun).
I love my second hand breadmaker, though. It gets used every couple of days and is quicker than walking round the corner to buy the manky pulp that is sold in supermarkets. With that comes my favourite 'gadget' - a set of balance scales that must be over 80 years old, are cast iron, look almost prehistoric and were missing the 1oz weights. However, as a 2p coin weighs exactly 1/4oz, I've got four of those on there.
The BM, SC and scales are the only things out at all times.