On further review, these are the ones that look interesting.
Bodyfeeder (+3): gain temp HP equal to half damage, Magic Item Compendium
Consumptive Burst (+3): negative level, Planar Handbook
Cursespewing (+3): -4 attacks, saves, and skills for 1 minute, Magic Item Compendium
Desiccating Burst (+1 synergy): fatigued, Magic Item Compendium
Doom Burst (+2): shaken for 5 rounds, Magic Item Compendium
Enfeebling (+1): 1d6+2 str damage (allows SR), Book of Exalted Deeds
Enervating (+2): negative level, Magic Item Compendium
Weakening (+1): -4 penalty str, Magic Item Compendium
Do you think a second critical hit with desiccating burst weapon makes the target fatigued? If not, how about a critical hit each from two desiccating burst weapons?