The ones I'm familiar with:

[="http://www.zzounds.com/item--PRCDB1"]ProCo DB1[/]="http://www.zzounds…"]ProCo DB1[/]

[[url=http://="http://www.zzounds…"]Whirlwind Director[/]="http://www.zzounds…"]Whirlwind Director[/]

[[url=http://[/URL]="http://www.zzounds…"]Countryman FET85[/]="http://www.zzounds…"]Countryman FET85[/]

Westcam (Hard to find, but worth it if you can).

I have a JDI from radial, I am liking it so far.

Afordable: Definitely Whirlwind
Not so afordable but better: JDI
Not affordable but a real good one: U5

Zoro
http://www.produccionestecate.com

I guess I should say too I find the JDI pretty transparent, it won't colour your tone. I would not suggest it if thats what your after.

So Whirlwind Director for the win?

i have a pro co db1 and am quite happy with it, but i havent used anything else to compare it to

I have the Whirlwind Director and I also had the Proco equivalent. I like them very much.

You may also want to search eBay for used UTC A-10 transformers? 50 kilo ohms input with multiple output windings for 50-600 ohm. Nice big and heavy. Really warm sounding. You stick it in a metal box and add connectors, a couple of switches and voilà!

Lover of all the DI's
Ms. Remy Ann David

ditto on what Remy said

you guys already know I love DIY

so
head to Jensen Transformers for some circuit ideas for DI boxes and re-amplification ideas

http://www.jensen-transformers.com/apps_sc.html

here is what they call the FULL FEATURED unit
http://www.jensen-transformers.com/as/as066.pdf
but
do look at the others and try to understand what they are doing with each one

it's simple stuff but you will learn things from each circuit idea

there are other circuit ideas out there on the net and this will include active units
search away
and have fun