Need more info. Stove what kind? Inside or out? Shower what material?
Hi Herb: For the stove, are you talking about burned on gunk?
What I use is a paste of vinegar and cream of tartar (the dry stuff). Make a paste of vinegar and cream of tartar (use just a bit of vinegar at first as the cream of tartar sort of melts) and put it on the gunk. Maybe start out with 3 tablespoons of cream of tartar and a 1/2 teaspoon of vinegar. Add more of whatever to make a paste. It should stick to a vertical surface if it's thick enough. Let it sit for about 15 or 20 seconds and then scrape off with a plastic putty knife or one of those plastic scrubbies. You may have to do it a couple of times if the gunk is thick, but usually not. There is no smell and it is environmentally safe. A lot of people don't know, but on most stoves, the door comes off and the bottom of the oven comes off. You don't have to take the door off to get the oven floor out. Sometimes it's hard to get the door back on:) Also, the rack holders are removable:) This also works really good on pots, pans and cookie sheets with a burnt on mess.
For the shower, believe it or not, spraying cooking spray on your shower door and walls will rid them of any soap scum and lime buildup. Just be sure to let it sit for a few minutes before wiping clean so it can really work its magic. Once you've finished cleaning your shower door and walls, make sure to scrub your shower floor with vinegar and water mixed 1/2 and 1/2 to prevent any slips or sliding.
If that's not something you want to try, here are a couple of sites that may help: