I finally bought round sponges!! Wasn't easy to find, but the ones with wooden handle are really comfortable.
After messing up with inks almost all the working table I used Fil's tips and scanned the textures I like most (with 600 dpi) After turning them into bitmap files I've added them to the illustration of Parvati (Hindu goddess) painted as a wall poster commission while ago.
With adding the grungy inky texture the illustration became more alive and eye-catching.
Using toned paper sometimes gives good results:)
There was no proper brush around so I've used pipette to pour inks to sponges.
One more neat thing about sponges - you can swirl your hand holding a wooden handle to get this awesome effect. It's like a fingerprints but without dirty hands:) was great to find that out during experimenting.
And here is the full illustration
Thanks! Glad to finally have a reason to buy sponges))