number of pages in google search for
iloans is 9,900
eloans is 255,000
itravel 1,830,000
etravel 697,000
ichat 2,550,000
echat 193,000
ihotel 215,000
ehotel 1,240,000
iflights 9,430
eflights 860
iprices 10,100
eprices 19,300
searches in overture
iloans 38
eloans 2,782
itravel 2,568
etravel 415
ichat 6,051
echat 178
ihotel 33
ehotel 58
iflights 0
eflights 81
I think therefore it varies considerably according to the term to which you apply the prefix.
If it in anyway makes sense (i chat for instance) then someone will have probably registered a brand with it some time ago and that may now have value.
even if it doesn't make sense, I think the development of previous brands is what is driving the traffic e.g. eloans (I don't think it means "he loans"!)
but edoes! (edoes.net avail)
Also in internet terms, e can mean email and i can mean internet, so that might twist it a bit.
m can mean mobile
-aqls-