The Reverse Index of the Dhammapada, Suttanipāta, Thera- and Therīgāthā Pādas with Parallels from the Āyāranga, Sūyagada, Uttarajjhāyā Dasaveyāliya and Isibhāsiyāiṁ by Willem B. Bollée from 1983 is a remarkable work.
It is an entire index of all the lines of all verses of the Dhammapada, Suttanipāta, Thera- and Therīgāthā and their parallels, also including parallels from the Jaina texts, sorted in pali alphabetical order of the last word of each line.
The most remarkable thing about this is that it is done entirely by hand, typed on a typewriter and most astonishing of all: it is right-aligned. Those of us who have still worked with a typewriter would understand the great achievement of just this fact.
I cannot upload the entire Reverse Index here; it is a scanned document of 88MB. But just to give an idea of what this text of 265 pages looks like:
So now our SC-Next development crashed last Friday afternoon, just before the weekend, I found myself with nothing much to do until our devas return on Monday morning. So I decided to go over this index and retrieve the Jaina parallels. Call me crazy but collecting Dhammapada parallels has become a hobby for me, and in this I found an ally in Venerable Anandajoti, who sent the Index to me a few weeks ago.
So I’ve uploaded the spreadsheet I used here. Just in case there is somebody else in the world so crazy as to be interested in this. I found a total of 16 (partial) parallels with the Jaina texts, excluding parallels of just one line.
bollee.ods.zip (20.3 KB)
As for the other parallels, I think we already have most if not all on SC.
Next time I find myself in need of a hobby, I will try to write a little python program to create a similar Reverse Index. It must have taken Mr. Bollée a lifetime but with more modern techniques I think I can do it in an afternoon 
