0.4 uploaded.
To use a previous result, simply type the "=" character. It can be used anywhere in your next calculation, so it's pretty handy.
For example:
1/7 0.14
=*54 7.56
75-= 67.44
sqrt(=) 8.21
Also added Cranio's fine suggestion of using >> for conversions:
2ft+6in>>cm 76.20 (76 1/5)
You can also use " as " and " to " but you do need the spaces around 'em:
10m as ft 32.81 (32 38/47) (32' 9.7")
10mi to ft 52,800.00 (52,800' 0")