Artisan (usually specialty) coffee roasting.
"…allows roasters to have more control over the roasting process, ensuring each bean reaches its peak flavor potential."
—Crockett Coffee
The small batch roaster is more interested in the quality of output than the quantity. Consider the needs of a local roaster versus, say, Starbucks. The quantities that Starbucks needs to produce to remain profitable means they have to roast coffee in industrial quantities, in excess of 100kg per roast cycle. It means larger machines, often cheaper beans and fewer opportunities to tweak a roast. Compare this with a small-batch artisanal roaster, who will often buy higher-standard beans directly from the grower, in smaller (sometimes experimental) lots, often seasonally sourced, and usually traceable. This coffee often is roasted in quantities between 1 and 15 kg, some roasters even roasting single kilograms to order. The attention to detail is apparent in the cup, as the roaster can take into account the unique qualities of the lot, the terroir, in order to get the very best flavour of of the batch.
Home roasters are by definition small-batch roasters. Most machines aimed at the market have capacities in the 500g - 2kg range, often identical to the sample roasters in use in commercial roasteries.
The rise of interest in specialty coffee means that enthusiast roasters can experiment with coffee roast styles as well as beans, and find a market for their product. For example, there's a young lad in my hometown who is roasting in very small batches (~1kg at a time, judging by his setup) and handling local distribution pretty much by hand. I'm looking forward to sampling his wares (my favourite cafe will be getting some of his beans in). I'm quite excited.
Further, many small cafes are taking the plunge into roasting in-house, and some equipment companies have even started developing roasting machines for that specific use case. My favourite local cafe is going to be doing roasting onsite soon, and I'm excited.
Harvey's coffee
$ xclip -o | wc -w
328