About 4 - 6 months ago i bought a brand new Mini Grinder/Engraver which i was going to use for porting my intakes on cars, my turbos aswell as cleaning up any metal jobs i did. At a price of about $15 Australian, the engraver is very cheap and comes in a handy carry bag. The kit contains the engraver, about 30 - 40 tips, varying from polishing ends, to grinding stores and diamond tip cutters.
The engraver runs off AC power and does not take any batteries, however for most specific uses this does not cause any dramas. As well as this, the speed can vary from about 100 - 200rpm, to 2000 -3000rpm, allowing a suitable speed for your job. An example of this is small grinding, and due to the nature, a high speed will be needed to cut the metal, however with engraving on weaker metals such as silver, a slower speed can be used to help minimise the chance of error.
As mentioned previously, the first job i did was port matching my intake manifold on a 3sgte engine, which involved using the grinding tips, as well as the polishing tips on the inside of the intake runners.
For any small jobs around the house that may pop up from time to time, this engraver is the product to buy, and at a price of $15, it can't be beaten. Most importantly, if it breaks within a year of purchasing the engraver, the product will be replaced for free by Solutions, as long as proof of purchase can be provided.