I'm a huge calligrapher user. I have lousy handwriting and this little beauty works like a champ. Add in penn commander with gesturing commands and it gets even better
http://www.phatware.com/calligrapher/index.html
Other good input items are:
Fitaly - a modified Keyboard SIP
http://www.fitaly.com
Full screen keyboards
http://www.spbsoftwarehouse.com/products/fsk/?en
There's a ton of others, checkout handango.com etc for SIPs