Wancher is a stationery maker which seems to have some existence in India and some in Japan. Their inks are extremely economical in and of themselves but as far as I know they are available only through an eBay storefront and thus shipping drives up the cost per ml. They do offer to combine shipping, so getting several colours at once helps keep things cheap. You’ll also be in ink for a good long time, as they appear to have given up on the 30ml vessels I bought mine in and offer only 100ml flasks. Update: Since I wrote this paragraph, the parties behind Wancher had moved to a website all their own– in addition to the inks, they’re flogging pens of their own brand and other accessories for the marginally anachronistic person.
The inks are generally well behaved, although there is a slight inclination towards feathering, and on higher quality papers they appear to not dry very briskly and profit from a quick blotting. These are paradoxical behaviours, since feathering and rapid drying are more usually associated. Despite this oddity of behaviour, I do recommend them; on the average paper, they don’t act up excessively, they’re nice to look at, and they don’t put up a great fight at pen-cleaning time.
Examples (note– I’ve not calibrated my scanner, so these are mere approximations of the true colour):
Asuka: named for a historical period in Japan, which the Wancher apparently feels is extremely connected with brownness. I don’t quite understand it myself, but it’s a nice, moderate, earthy brown.
Ebine: This is a rather bright magenta, although it does have some depth to it. It is pretty true to the orchid from which it gets its name.
Imari: a pleasant medium blue, whose name is the Japanese version of “Delft”– a locale become synonymous with the pottery produced there. This is probably the best behaved of the Wancher inks that I’ve got.
Matcha: an interesting green, leaning in the direction of yellow, very much the colour of new leaves; appropriate, I suppose, for an ink named after green tea.