"According to the publishers, it would take a single person 120 years to 'key in' text to convert it to machine readable form which consists a total of 59 million words of the OED second edition, 60 years to proofread it, and 540 megabytes to store it electronically. As of 30 November 2005, the Oxford English Dictionary contained approximately 301,100 main entries. Supplementing the entry headwords, there are 157,000 bold-type combinations and derivatives; 169,000 italicized-bold phrases and combinations; 616,500 word-forms in total, including 137,000 pronunciations; 249,300 etymologies; 577,000 cross-references; and 2,412,400 usage quotations. The dictionary's latest, complete print edition (Second Edition, 1989) was printed in 20 volumes, comprising 291,500 entries in 21,730 pages."
That's 375 floppy disks.
J. R. R. Tolkien was employed by the OED, researching etymologies of the Waggle to Warlock range.
An odd note: In High School, I accidentally dropped Follow-Hat in the library. It landed exactly flat and sounded like the crack of doom.
I do have two copies, the First & Second Editions. The Second is on CD and doesn't hurt my back at all.