For a while now I have known about cleaning bathrooms with baking soda and water, which you just combined into a thick paste and used on walls, grout, etc. I haven't actually ever used it, but thought I would give it a try on my bathroom the other day, which was looking a little grey for all the mould in the grout.
I have some "special" cleaning paste (suppose to be natural) and microfibre cloths which I normally use, but thought it looked a little too much like hard work. So, I had an old toothbrush and I thought I would give the baking soda paste a try.
Wow, how fabulous is it to clean grout and bathrooms generally with a toothbrush. The baking soda paste didn't completely eliminate the grim, but certainly improved the darkness and I am so impressed with the ease of toothbrush cleaning I didn't mind giving it another go this weekend just past. And managed to experience another "enjoyable" cleaning moment.
My only problem is old toothbrush don't last with the amount of pressure applied and I really need a large amount of them to continue to get into my grout gaps effectively. So, if you've got some spare and you don't cotton on to this less laborious cleaning practice, send me your old toothbrushes!